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Nhận dạng hạt thóc giống sử dụng kĩ thuật xử lý ảnh và thị giác máy tính

Phan Thi Thu Hong, Tran Thi Thanh Hai, Le Thi Lan, Vo Ta Hoang, Nguyen Thi Thuy

Received: 22-07-2015 / Accepted: 03-09-2015
Bài báo này giới thiệu về một hệ thống tự động nhận dạng hạt thóc giống phục vụ cho quy trình sản xuất thóc giống ứng dụng kĩ thuật xử lý ảnh và thị giác máy tính. Hạt thóc của những giống lúa khác nhau khi nhìn bằng mắt thường là rất giống nhau về màu sắc, hình dáng và kết cấu bên ngoài. Điều đó làm cho việc phân biệt các loại thóc giống khác nhau với độ chính xác cao nhằm đánh giá độ thuần chủng của thóc là một thách thức lớn. Chúng tôi tập trung vào các kĩ thuật khác nhau để trích chọn đặc trưng hình ảnh của hạt thóc giống thông qua ảnh chụp các giống lúa một cách hiệu quả. Sau đó chúng tôi phân tích hiệu năng của các bộ phân loại dựa trên các đặc trưng được trích chọn ở trên để tìm ra một phương pháp phân lớp có độ chính xác cao nhất. Hình ảnh của sáu giống lúa khác nhau đã được thu nhận ở miền Bắc Việt Nam, trong đó mỗi giống có từ 1026-2229 hình ảnh hạt lúa. Những thực nghiệm của chúng tôi đã chỉ ra rằng hệ thống phân lớp đạt độ chính xác cao nhất 90.54% khi sử dụng phương pháp rừng ngẫu nhiên dựa trên bộ đặc trưng cơ bản. Kết quả này có thể sử dụng để phát triển một hệ thống thị giác máy tính hỗ trợ việc đánh giá tự động độ thuần chủng của hạt thóc giống.
Evaluating The Growth and Yield of Oyster Mushroom Strains (Pleurotusspp.) Cultured on Rice Straw

Nguyen Thi Bich Thuy, Nguyen Thi Lam Hai, Nguyen Thi Luyen, Tran Dong Anh, Nguyen Van Giang, Nguyen Thi Ngoc

Received: 09-06-2017 / Accepted: 12-12-2017
Oyster mushroom (Pleurotus spp.) is a delicious edible fungus with high nutritional and medicinal values. Itcontains all essential amino acids and several polysaccharides.Five strains of oyster mushroom werecultivated on rice straw sterilized at 121oC for 100 min and on rice straw piled for6-7 days at 60-70oC. The results showed that of5 oyster mushroom strains, PN1 showed the highest growth rate. In addition, sterilized straw was the most suitable material for the growth of PN1 with bio-efficiency at 73.8%. For further investigation, PN1 was cultured on a mixture of different materials including straw and some agricultural wastes such as cotton seed hull, sawdust, husk, and rice bran. It showed that the mix(in percent) with straw (84), cotton seed hull (10), rice bran (5) and CaCO3(1)was the best medium for the mycelial growth and fruitingbody yield and the bio-efficiency of PN1reached 77.4%.
Agricultural Land Use Change towards Improving Value Added in Nam Sach District, Hai Duong Province

Nguyen Thi Phuong Duyen, Nguyen Thi Vong, Nguyen Tuan Anh, Nguyen Quang Huy

Received: 27-09-2017 / Accepted: 28-03-2018
A study was conducted to analyze the current status of agricultural land utilization and find solutions for restructuring the agricultural sector in terms of agricultural land use change in Nam Sach District, Hai Duong Province. Secondary and primary data collection were collectedin the study. Multi-objective optimization model was used to determine the area of 31 actual land utilization types serving as basis for change in the land use towards higher value added. At present, there were 8 land use types (LUTs) and 31 land utilization types, in which the area of two rice crops was largest with 2,480.71 ha, accounting for 34.65% of the total agricultural land. Based on the results of multi-objective optimization model analysis, the evaluation of efficiency of current land use and agricultural development orientations of the district, the areas under two rice crops (1,180.71 ha), aquaculture (505.19 ha), and rice -non-rice crops (52.75 ha) are recommended to change to two rice - non-rice crops, integrated farms, and fruit production, respectively.
Evaluation ofSalt Tolerance of Newly Collected Rice Accessions

Nguyen Anh Dung, Vu Van Liet

Received: 27-11-2023 / Accepted: 07-03-2024
This study was carried out to evaluate agronomic characteristics, salttolerance and the presence of QTL Saltolof newly collected rice accessions throughfield experiment,artificial salinity treatment and molecular identification. The experiments on agronomic characteristics and salt tolerance were carried out according to the method of IRRI, 1997 and 2013 at the FieldCrops Research Institute, Gia Loc district, Hai Duong province whilemolecular marker analysis was conducted at Vietnam National University of Agriculture, Gia Lam district, Ha Noi city. Theevaluation results showed that the rice accessions were diverse in growth duration, plant height, flag leaf length, and panicle length. Out of 39 accessions, 6 promising ones were selectedwith good salt tolerance: Lua soi, M3, HHZ8-SAL6-SAL3-SAL1, HHZ8-SAL6-SAL3-Y2, HHZ12-SAL8-Y1-SAL1 and Hasawi IRGC 16817and 22 rice accessions carrying SaltolQTL. Thus, the selection of materials for breeding salt-tolerant rice varieties should combine the evaluation of agronomic characteristics with artificial salt tolerance assessment and molecular markers.
Evaluation ofSalt Tolerance of Newly Collected Rice Accessions

Nguyen Anh Dung, Vu Van Liet

Received: 27-11-2023 / Accepted: 07-03-2024
This study was carried out to evaluate agronomic characteristics, salttolerance and the presence of QTL Saltolof newly collected rice accessions throughfield experiment,artificial salinity treatment and molecular identification. The experiments on agronomic characteristics and salt tolerance were carried out according to the method of IRRI, 1997 and 2013 at the FieldCrops Research Institute, Gia Loc district, Hai Duong province whilemolecular marker analysis was conducted at Vietnam National University of Agriculture, Gia Lam district, Ha Noi city. Theevaluation results showed that the rice accessions were diverse in growth duration, plant height, flag leaf length, and panicle length. Out of 39 accessions, 6 promising ones were selectedwith good salt tolerance: Lua soi, M3, HHZ8-SAL6-SAL3-SAL1, HHZ8-SAL6-SAL3-Y2, HHZ12-SAL8-Y1-SAL1 and Hasawi IRGC 16817and 22 rice accessions carrying SaltolQTL. Thus, the selection of materials for breeding salt-tolerant rice varieties should combine the evaluation of agronomic characteristics with artificial salt tolerance assessment and molecular markers.
Effects of Nitrogen FertilizerLevels on Content and Quality of Rice Bran Oil in JaponicaRice Line with Thick Aleurone Layer

Nguyen Hoang Phuong, Nguyen Thi Thu Hien, Nguyen Thi Quyen, Nguyen Duc Thuan, Nguyen Van Khoa, Pham Van Cuong

Received: 19-05-2023 / Accepted: 29-06-2023
A pot experiment was carried out in net house to evaluate the effect of nitrogen fertilization levels (0.5; 1.0 and 1.5g N per 0.03m2pot) on photosynthesis, grain yield and bran oil of the promising line with thick aleurone layer (Ja12) and the check variety (the original Mizuhochikara) in both autumn and spring season. The photosynthetic rate was measured in 5 plants of each treatment at flowering, milkand dough stages while whole plant dry matter accumulation was measured in five plants at effective tillering, booting, dough and mature stages. At the harvesting stage, the grain yield, ratio of bran/brown rice, and oil content were analysed in 20 plants of each treatment.The experiment results showed that photosynthesis rate and dry matter accumulation increased in both rice varieties with increasing N fertilizer level. The grain yield and characteristics related to oil quality including lipid content and γ-oryzanol content ofJa12 were higher than those ofthe check variety at all fertilizer levels in both cropping seasons. Increasing the amount of nitrogen fertilizer did not increase the ratio of bran/brown rice but increased the content of bran oil and the γ-oryzanol content in both rice varieties, especially the increase was much higher in Ja12 than that in Mizuchihokara variety in both cropping seasons.
Evaluating Rice Crop Insurance Demand in the Mekong Delta

Nguyen Van Tac, Nguyen Tri Khiem

Received: 16-01-2023 / Accepted: 03-04-2023
To contribute to the development of rice crop insurance in the Mekong Delta, this study aimed to estimate the willingness to pay and identify the factors affecting the willingness to pay of rice farmers. Thestudy was conducted through the insurance scenario of rice yield index due to weather, climate and disease risks by contingent valuation method in the form of double-bounded dichotomous choice. The article data were collected from direct interviews with 463 rice farmers in the Mekong Delta in 2019. Results show that 47.5% of respondents agreed with both the first premium and the next higher premium when asked while 17.1% of individuals disagreed with both premiums even though the second was recommended lower and 35.4% of other cases. The average willingness to pay was estimated to be 68.633 VND/1,000m2/crop. The research results also pointed out the factors affecting the willingness to pay of rice farmers such as education, production costs, dikes, selling price, loans, other incomes and risk response.
Designing CRISPR/CAS9 System for Knocking out OsNRAMP5Related to Cadmium Accumulation in Rice Variety TBR225

Ngo Thi Van Anh, Nguyen Anh Minh, Pham Thu Hang, Pham Phuong Ngoc, Le Quynh Mai, Pham Xuan Hoi, Nguyen Duy Phuong

Received: 06-08-2022 / Accepted: 27-09-2022
Cadmium (Cd) is highly toxic to most living organisms, including humans. Rice with excessive Cd (> 0,2 mg/kg - QCVN 8-2:2011/BYT) is one of the leading causes of Cd poisoning, threatening human health. Several genes belonging to the NRAMP(natural resistance-associated macrophage protein) family are related to metal accumulation in plants; in which OsNRAMP5has been identified to be involved in the transport of various metals such as iron (Fe), zinc (Zn), copper (Cu), manganese) Mn and Cd in rice. In order to identify the function of OsNRAMP5in elite rice variety TBR225, we evaluated the expression of the targeted gene and designed Clustered regular interspaced short palindromic repeats/CRISPR-associated Cas9 (CRISPR/Cas9) system for editing TBR225OsNRAMP5. The increase of OsNRAMP5expression was observed in the root tissues of TBR225 rice plant in the Cd-treatment experiment using hydroponic culture. A sequence containing the ExonI region of OsNRAMP5with a size of 0.29kb was isolated from the total DNA of TBR225 to design single guide RNAs (sgRNA) for OsNRAMP5-editingCRISPR/Cas9 system. The sgRNA expression construct carrying two CRISPR RNA (crRNA) sequences recognizing two different sites on the ExonI of OsNRAMP5was ligated into the binary vector pCas9. The recombinant vector was validatedby PCR and sequencinganalysis. The results serve as basis for the improvement ofTBR225 rice variety with high quality byusinggenome editing technology.
Salt Tolerance of Rice Varieties at the Germination and Seedling Stages

Vu Thi Xuan Nhuong, Nguyen Thien Minh, Dang Huu Tri, Nguyen Chau Thanh Tung, Huynh Ky, Ngo Thuy Diem Trang

Received: 23-02-2022 / Accepted: 05-07-2022
The study was conducted to evaluate salinity tolerance of four rice varieties, OM5451, IR29, OM18 and MTL316 at germination and seedling stages in four NaCl salinity concentrations of 0, 2, 4 and 6‰. The experiment was arranged in a completely randomized design with three replications in the net house. Irrigation with 4-6‰ salinity solutions (EC = 7.4-10.1mS/cm) reduced germination rate and growth characteristics of four rice varieties at the germination and seedling stages, respectively. The shoot and root fresh weight of salt-treatment derived young seedlings and seedlings of OM5451 reduced less than the other three rice varieties as compared to the control (untreated seedlings). Na+content was accumulated mainly in the shoots. The results indicated that OM5451 had higher salt tolerance than other three rice varieties at both germination and seedling stages.
Factors Affecting Intention to Choose Crab - Shrimp - Rice Farming Model in Kien Giang Province

Le Ngoc Danh, Nguyen Thi Kim Phuoc, Le Hong Hanh

Received: 06-09-2021 / Accepted: 21-01-2022
The study uses a binary regression model, rational action (TRA) theory, and the theory of intentional behavior (TPB). The study's objectives are to determine the factors affecting the intention to choose the farming model of crab - shrimp - rice of farmers in Kien Giang province. The results of the analysis of 102 extensive crab-shrimp-rice farming households showed that male respondents accounted for 82.4%, the average age of the household head was 51 years old, the average education level of the household head was 7th grade. The average number of years of experience of the household head was 10 years, the average area of the household was 2.8 ha. The results of binary regression analysis showed that 9 variables (education, training, experience, area, salinity, increased profit, model fit, impact of people around, and model implementation ease) influenced the intention to choose the farming model of crab-shrimp-rice of farmers. From the research results, the following solutions were proposed: Farmers’ management of all kinds of risks during the productionand consumption of shrimp and rice,regular monitoring of weather/environmental studies or forecasts,selection of seed sources and inputs (feed, lime, antibiotics) from reputable establishments,participating in local trainingandsqueezing the shrimp back before putting them in the pond.
Breeding New Promising Mutant Rice Lines by Gamma Co60

Nguyen Thi Mien, Nguyen Trong Khanh, Tran Van Quang

Received: 05-08-2021 / Accepted: 09-12-2021
This study was carried out to evaluate agronomic characteristics, yield, and quality of inbred rice lines that have been selected from the segregated M2populations derived from gamma (Co60) irradiation on imported rice varieties. The field experiments were conducted at Field Crops Research Institute, Haiduong province, Vietnam. Out of 20 inbred lines, there are three promising lines have been selected with good agronomic characteristics such as: short growth duration, low plant height, light pest infestation, high yield, high ratio of milling yield, and low amylose content. The new line NN1-2-6-55, which derived from gamma Co60irradiated segregating the population of accession rice NN1, had a desirable growth duration of 129 days in spring and 100 days in summer season, slight pest infestation, good lodging resistance, harvested yield of 6.75 tons ha-1in spring and 6.07 tons ha-1in the summer crop season with milling yield reached of 70% and preferred eating quality with an amylose content of 14%. Consequently, the improving of growth duration, plant height of import materials could be used gamma radioactive Co60 for mutation.
Evaluating the Impacts of Rice Value Chain Upgradingin Three Sub-Regions of the Mekong Delta

Tran Minh Hung, Le Canh Dung

Received: 20-04-2021 / Accepted: 15-07-2021
This study evaluated the general impacts of the value chain upgrading process and the positive aspects of the upgraded value chain in comparison with the value chain of external cooperatives/cooperative groups. The chain upgrading process was conducted in three cooperatives/cooperative groups categorized into three types of value chains, including open chain, linked chain, and closed chain. The product lines selected for the chain upgrading based on the classification of the Vietnam Food Association (VFA) consisted of two groups. The first one involved specialty rice that is fragrant, soft, and of high quality such as ST24, Dai Thom 8, and Jasmine 85. The second group consisted of long-grain white rice with light fragrance and high quality. The expansion models (MHMR) followed VietGAP, SRP, and organic standards in rice cultivation to meet the market needs. In the course of organizing global value chains, the connection between the market represented by export enterprises and raw material areas is essential. It becomes a primary condition to upgrade the value chain, in which risk and benefits sharing must be discussed and maintained over the long term. This contributes to create standardized products according to the current market needs and to affirm the Vietnamese rice brand.
QTL Mapping for Agronomical Traits of VietnameseRice Landraces (Oryza sativaL.)

Nguyen Thi Thuy Hanh, Nguyen Trung Anh, Nguyen Quoc Trung, Pham Van Cuong

Received: 10-06-2020 / Accepted: 10-08-2020
Inattempts to generate high-yield and good-quality rice varieties to ensure food security in the context of reducing rice-growingareasdue to the urbanization process and the current agricultural restructuring in Vietnam, the genetic informationof rice landracesat the molecular level is essential. In this study, QTLs were identified with some agronomic traits inrice varieties being grown in Vietnam by analysing data of plant height, number of tillers and total dry weightand QTL Cartographer version 2,5soft ware. The result showed 12 QTLs for plant height, number of tillers and total dry weight onthechromosomes 1, 2, 4, 7, 9 and 10. The QTL for plant height on chromosome 2 was the QTL with a high LOD value and ahigh percentage of phenotypic variation explained by 5.23 and 39.81%, respectively. This QTL has been identified in several other independent researches. These results might provide useful information for rice breeders and will be an important basis for further research to identify genes that regulate plant height traits in rice varieties grown in Vietnam.
Breeding and Developing the Inbred Rice Cultivars ĐH12 for Northern Vietnam

Tran Van Quang, Nguyen Thi Kim Dung, Nguyen Thi Dong, Le Van Huy, Ha Van Duyen, Nguyen Mai Anh, Tran Thi Huyen

Received: 11-02-2020 / Accepted: 09-04-2020
This study was carried out to breed the inbred variety with short grown duration, high yield, good quality and lightpest-resistant for Northern region of Vietnam. The DH12 was developed from segregational populations, which have derived from R2/R9311 line combination and selected by the pedigree method. DH12 has a short grown duration, 130-135 days in the spring season, 105-110 days in the summer season, 98-102 days in the Autumnseason. DH12 has good characteristics such as averageplantheight, roll flat leaves and light diseases infection. In field trials, DH12 has yield 7.2-7.8 tons/hectare in the spring season, 6.5-6.8 tons in summer season and 5.8-6.0 tons in the autumnseason, higher than controlvariety (Khang dan 18) from 10.1 to 22.0%. DH12 has milling rice 63.34%, head rice recovery 58.64%, long grain 6.9 mm, slender grain and good cooking quality. Thus, the breeding through cross hybrid between quality rice variety and intensive variety, and was selected by pedigree method, which can create new rice variety, has good quality, high yield and suitable cultivable with the conditions in northern Vietnam.
Direct and Indirect Effects of Some Agronomical Traits OnInvidual Yield of Salt-Tolerant Rice in Thua Thien Hue

Nguyen Ho Lam

Received: 31-07-2017 / Accepted: 23-01-2018
This study was conducted to determine relationshipamong agronomic traitsand their contribution to plant grainyieldofsalt-tolerant rice cultivars in Central Vietnam. The experiment was arranged directly on saline soils at an average salinity level of 6.35 dS/m in 2017 winter-spring croppingseason in Thua Thien Hue with 10 popular salt-tolerant rice cultivars. Of all the agronomictraits studied, individual yields had a positive correlation coefficient with plant height (0.3624*), total panicles/plant (0.7019***), panicle weight (0.4530**) and total dry biomass (0.7837***). Total panicles/plant and panicle weight directly affect on the formation of rice yield. Total dry biomass and plant height do not directly affect yield, but are indirectly throughpanicle weights and total grains/panicle. Therefore, total number of paniclesper plant, panicle weight and total number of seedsper panicle would be effective selection criteriafor improvement of salt-tolerant rice cultivars in the central region.
Evaluation of Growthand Yield of Four Rice Varieties Grown in Agro-Ecological Zones of Acid Sulphate Soils in The Mekong Delta

Nguyen Quoc Khuong, Nguyen Kim Quyen, Nguyen Van Nghia, Lam Ngọc Phuong

Received: 03-12-2016 / Accepted: 14-04-2017
The objective of this study was to evaluate the growth and yield of rice varieties grown indifferent agro-ecological zones in different croppingseasons. Four rice varieties were MTL547, OM 517, OM 921 and OM 347. Results showed that variety OM7347 had highest plant height, grain number per panicle, filled grain percentage and yield within agro-ecological zones of acid sulphate soils (ASS) while variety OM9921 was lowest in growth and yield at three sites of Hon Dat, Hong Dan and Thap Muoi. For Phung Hiep, yield of MTL547 was lowest. Phung Hiep ASS was the most constraints due to low pH, low available phosphorus, and high exchangeable aluminium. The number of panicle per square metre, grain number per panicle and filled grain percentage indry season(DS)rice werehigher than those inwet season rice. As a result, the yieldinthe DS was higher than at least 2.5 tons per hectare compared to that inthe wet seson (WS), although the fertilizers applied per hectare (kg N - kg P2O5 - kg K2O) for dry season crop (100-60-30) was slightly different than that in WS(80-60-30).
Evaluation on Drought Tolerance of Rice Lines with Indica Genetic Background Carrying Chromosome Segment Substitution from Wild Rice (Oryza rufipogon)or Japonica

Pham Van Cuong, Doan Cong Dien, Tran Anh Tuan, Tang Thi Hanh

Received: 21-10-2014 / Accepted: 10-03-2015
Twenty chromosome segment substitution lines (CSSLs) developed from IR24 background (5 lines of Ruf ILs (IR24 × O. rufipogon), 15 lines of IAS (IR24 × Assominori - a Japonica cultivated rice) and IR24 were evaluated for drought tolerance at tillering stage. The 3-leaf seedlings were grown in Kimura B + 20% PEG6000 solution (drought treatment) or in Kimura B solution (non-drought treatment). The results showed that, the drought resistance index (DRI) correlated with the dry matter under drought and non-drought conditions with r = 0,614 and r = 0,604, respectively. The number of leaves, leaf area, root surface area, number of roots and root hairs in both CSSLs and IR24 were reduced in drought condition. But, there was no reduction in root numbers and root hairs numbers in CSSLs, which had higher DRI. The results also showed that, drought tolerance mechanism of IAS lines might involve the increase of root growth, water uptake and root-to-shoot water transport. However, the mechanism in Ruf ILs lines might involve the reduction of leaf number, leaf area and in company with increase of root growth and water uptake. These finding suggested that wild rice O. rufipogon and Asominori would be ideal materials for rice breeding for drought tolerance.
PHYSIOLOGYCAL RESPONSES OF RICE SEEDLINGS UNDER DROUGHT STRESS

Phung Thi Thu Ha

Received: 02-06-2014 / Accepted: 15-08-2014
Lúa là một trong những cây lương thực quan trọng bậc nhất trên thế giới. Trong nghiên cứu này chúng tôi nghiên cứu phản ứng sinh lý của giống lúa Oryza sativacv. Dongjin trong điều kiện khô hạn. Kết quả nghiên cứu cho thấy,cây lúa 3 tuần tuổi bắt đầu biểu hiện kiểu hình lá cuộn lại và khô sau 48h dừng tưới nước. Cùng với sự mất nước trong lá và giảm thế hóa nước trong thân,các gốc tự do như H2O2và malondialdehyde cũng được tích lũy. Điều đó dẫn tới hiệu suất quang hợp giảm mặc dù hàm lượng chlorophyll giảm không đáng kể.
Molecular Marker for Using to Detect Fragrant Gene in Aromatic Rice Breeding

Duong Xuan Tu, Nguyen Van Khoi, Le Thi Thanh, Nguyen Thi Huong, Nguyen The Duong, Tran Thi Dieu, Phan Huu Ton

Received: 29-04-2014 / Accepted: 18-07-2014
DNA markers RG28, RM223, RM342, L06 and BADH2 comprising 4 primers EAP, ESP, IFAP, INSP have been reported closely linked to fgr gene located on chromosome 8 controlling 2AP synthesis, major materials producing aroma in rice. In our report, marker BADH2 (4 primers EAP, ESP, IFAP, INSP) yielded in high polymorphism and could accurately differentiate between fragrant and none-fragrant rice material. Analysis of F2 population derived from cross between aromatic and non-aromatic rice varieties using this marker showed approximate ratio of segregation of 1: 2 : 1 . Using this marker, from 92% to 95% of F2 individuals expressing aroma in grains were identified as homozygotes for fgr gene. These results confirmed the accuracy of BADH2 marker with 4 primers EAP, ESP, IFAP, INSP to detect fragrant gene in aromatic rice breeding materials.
Study on Sequences of Gene Encoding Lea Protein in Some Salt Resistant Rice Varieties

Tran Xuan An, Dang Xuan Nghiem, Tang Thi Hanh, Pham Van Cuong, Do Thi Phuc

Received: 13-05-2014 / Accepted: 15-07-2014
LEA protein comprises a large group of proteins which highly accumulates in plant seeds at late stage of maturation. LEA protein is proven to be involved in abiotic stress responses in plants, such as under dehydration and salinity. Genes encoding LEA proteins are divided into 6 different groups. Lea21 gene belongs to group 5. Up to now, there is no report about sequence polymorphsim of Lea21 gene in Vietnamese rice varieties. Therefore, in order to investigate the genetic diversity in rice, Lea21 gene from some salt resistant rice varieties was amplified and sequenced. The Lea21 gene, which consists of 2 exon and 1 intron, was sucessfully amplified using PCR technique and was sequenced.. It was shown that no difference in nucleotide sequences among investigated rice varities was observed, indicating that the sequence of Lea21 gene is highly conserved.
Ảnhhưởngcủacácđộẩmđấtkhácnhauđếnsinhtrưởngvàhiệuquảsửdụngnướccủamộtsốgiốnglúa(OryzasativaL.) ở giaiđoạncâycon

Nguyen Thi Ngoc Dinh, Nguyen Van Loc, Toshihiro Mochizuki

Received: 14-04-2014 / Accepted: 20-05-2014
Thí nghiệm nghiên cứu ảnh hưởng của độ ẩm đất đến các đặc điểm sinh trưởng và hiệu quả sử dụng nước ở giai đoạn cây con của 6 giống lúa (Oryza sativar L.) (Beodien, KD18, Koshihikari, Sensho, Rayada). 5 ngày sau gieo hạt, tỉa để lại 1 cây ở mỗi chậu và bắt đầu xử lý độ ẩm đất với 3 mức: đối chứng là cho ngập nước; duy trì độ ẩm đất 24% (24%SMC)-độ ẩm tối ưu; độ ẩm đất 12% (12% SMC)-hạn. Kết quả của thí nghiệm chỉ ra rằng, khối lượng chất khô của thân lá (SDW), khối lượng chất khô của rễ (RDW), tổng khối lượng chất khô của toàn cây (TDW), diện tích lá (LA), lượng nước sử dụng (WU) và hiệu quả sử dụng nước (WUE) của 4 giống Rayada, Sensho, KD18, IR24 không có sự sai khác có ý nghĩa 95% giữa công thức đối chứng và công thức độ ẩm đất 24%. Hai giống Koshihikari và Beodien ở công thức độ ẩm đất 24% cho giá trị thấp hơn so với công thức đối chứng đối với các chỉ tiêu trên. Ở công thức độ ẩm đất 24% và 12%, tổng chiều dài rễ (RL), diện tích bề mặt rễ (RSA) có khuynh hướng tăng ở hầu hết các giống trừ giống Koshihikari. RL, RSA, thể tích rễ (RV) của giống Koshihikari trong điều kiện hảo khí thấp hơn công thức đối chứng. Giống Rayada đạt giá trị về RL, RSA, RV, SDW, TDW, LA và WU cao nhất so với các giống còn lại, kế đến là giống Sensho. Ngoài ra, giống Rayada còn đạt giá trị cao nhất về hiệu quả sử dụng nước (WUE) trong điều kiện hạn, kế đến là giống Sensho. Hai giống KD18, IR24 có giá trị về LA, SDW, RDW, TDW và WU thấp hơn so với các giống còn lại ở tất cả các công thức. Tuy nhiên, trong điều kiện hạn thì hai giống này không bị ảnh hưởng nhiều như các giống còn lại. Từ kết quả thí nghiệm cho thấy rằng hai giống Rayada, Sensho phù hợp với hệ thống canh tác hảo khí, giống Koshihikari không phù hợp. Giống lúa nước indica KD18 và IR24 thích hợp với điều kiện hạn hơn giống lúa nước japonica Koshihikari.
Comparison of Some Quality Paddy Varieties in Spring Crop at Muong Thanh Field, Dien Bien District

Hoang Cong Menh, Hoang Tuan Hiep, Pham Tien Dung

Received: 01-03-2013 / Accepted: 18-04-2013
An experiment was conductedonFluvisols Acrisoil duringspring rice from 2011to2012in the the Muong Thanh field,Dien Bien District to compare the quality ricevarieties. The study used three quality rice varieties: HT6, T10 andSH2 and Bac Thom N07 was used as control.Thecultural practices applied tothe experiments, such as seeding rate, crop management, and harvesting was based on the average oflocal farmers. The experiments werearranged in Randomized Complete Block (RCB) and repeated thrice. Growth, yield, and culinary quality were recorded and evaluated. The experimental results showed that HT6 rice variety has highest yield (averageyieldof7.12 tons/ha), higher thanthe control by 11.6%. (P =0.05). HT6 variety brought the highesteconomic efficiency(net profit of VND 37.7million/ha). Qualityanalysis showed that rice variety HT6 has low amylose content, high gel strength, especially, good eating quality with a typical aroma. After cooking rice remains soft, shiny, good adhesive and smooth. HT6 varitey is recommended to the large scale production.
Xác định độ tiêu hóa của một số nguyên liệu thực vật đối với cá trắm cỏ (Ctenopharyngodon idella)

Tran Thi Nang Thu

Received: 30-10-2012 / Accepted: 22-12-2012
Nghiên cứu này nhằm mục đích xác định độ tiêu hóa của cá trắm cỏ (Ctenopharyngodon idella) đối với 3 loại nguyên liệu là cám gạo, bột ngô và bột sắn. Việc xác định độ tiêu hóa của các dưỡng chất trong các nguyên liệu có nguồn gốc thực vật được thực hiện theo phương pháp gián tiếp có sử dụng chất đánh dấu Cr2O3. Cám gạo cho kết quả cao về độ tiêu hóa vật chất khô (80,3%), protein (87,9%) và chất khoáng (97,4%). Tương tự bột ngô cũng cho kết quả khá cao về độ tiêu hóa vật chất khô (88,9%), protein (84.9%) và chất khoáng (92,7%). Không có sự khác biệt có ý nghĩa thống kê khi so sánh độ tiêu hóa các dưỡng chất của cám gạo và bột ngô đối với cá trắm cỏ. Độ tiêu hóa chất khô, protein và chất khoáng của bột sắn lần lượt là 80,3%, 87,9% và 14,3% và thấp hơn so với của cám gạo và bột ngô. Kết quả bước đầu này cho thấy cá trắm cỏ tiêu hóa cám gạo và bột ngô tốt hơn bột sắn.
Study on Plant Regeneration from Embryo of a Group Varieties of Upland Vietnamese Rice for Transformation Approach

Phan Thi Thu Hien

Received: 15-02-2012 / Accepted: 16-07-2012
A total of 31 upland rice varieties with low yield but good drought tolerance potential was used to examine their culturabilty in vitro(callus induction and plant regeneration) and to preliminarily establish genetic transformation protocol. Of 31 rice varieties, 25 have good callus formation with a induction rate of more than 50% and four of them have very high callus formation rate, varying from 76.3% (Khau tram họm variety) to 85% (Khau cong ton variety). The MS medium supplement with 1.5-2mg/l 2,4D seemed to be optimal for callus induction while supplement with 2mg/l BAP, 0.5mg/l kinetin and 0.1mg/l casein was optimal for plant regeneration. Analysis of variance (ANOVA) showed that the callus forming potency and plant regeneration capacity of these rice accessions were influenced by culture media and genetic background (genotype). The gene OsDREB2ACAwas successfully tranformed using Agrobacterium tumefaciens into Khau tram hom variety.
Species Composition and Abundanceof Zoobenthosinthe Rice Field Area inTri TonDistrict, An GiangProvince

Au Van Hoa, Nguyen Thi Kim Lien, Tran Huynh Khanh, Tran Van Dung, Nguyen Minh Dong, Huynh Truong Giang

Received: 12-08-2022 / Accepted: 21-10-2022
The study aimed to determine the species composition and abundance of zoobenthos in the paddy fields in Tri Ton district, An Giang province. Zoobenthos samples were collected at 6 sites consisting of 3 sites in the rice field area with 2 crops/year (TV1) and 3 sites in the rice field area with 3 crops/year (TV2) within 4 months. The sampling period began in December 2020, March 2021, November 2021 and February 2022. The results showed a total of 11 species belonging to 9 genera, 7 families, 6 orders, 4 classes and 3 phylums. The number of species in the sampling sites varied from 2 to 7 with a density ranged from 7 to 1,283 ind/m2. The number of benthic species in TV1 was higher than that in TV2. In contrast, the density of zoobenthos in TV1 was 7 times lower compared to that in TV2. The average d and J' indices ranged from 0.4-0.9 and 0.5-0.8, respectively, indicating high diversity and uniformity of benthic density in TV1 and TV2. Shannon diversity index (H') ranged from 0.2 to 1.7, indicating that the zoobenthos diversity richness found in TV1 and TV2 was from low to moderate. The results showed that different rice farming activities affect the distribution of species composition and abundance of benthic organisms in the rice field area at Tri Ton district, An Giang province.

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