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Low oxidative stability, off-flavor and rancidity are the major drawbacks of soybean oil. Modification of the fatty acid composition of soybean [Glycine max (L.) Merrill] oil can improve its quality and value for processors and acceptability among consumers. Mutation breeding of soybean was therefore initiated with the objective of identifying stable soybean mutants with altered fatty acid composition for improved oxidative stability and nutritional quality. Seeds of soybean cultivar 'MACS 450' were treated with c-radiation and/or ethyl methane sulfonate (EMS). The harvest of M 1 plants was evaluated for fatty acid composition by gas chromatography. Highly significant variation in all the fatty acids except palmitic acid was observed. Treatment of EMS in higher concentrations as well as combined treatment of both the mutagens, i.e., c-radiation and EMS were effective in increasing the variability for the fatty acid content in soybean oil. The variability was skewed towards high levels of oleic (35-42%) and low levels of linolenic acid (3.77-5.00%). M 3 and M 4 generations of desirable variants were analyzed for the stability of the mutated trait . Only high oleic variants were stable in M 3 and M 4 generations. Based on fatty acid values, oxidative stability index (OSI), nutritional quality index (NQI) and ratio of essential fatty acids (x 6 / x 3 ) were calculated for the control and M 2 , M 3 and M 4 generations. The x 6 /x 3 ratio in all the high oleic mutants was within the World Health Organization (WHO) recommended value (5-10%). A significant positive correlation between OSI and oleic acid content (P \ 0.001) indicated improved oxidative stability of the oil while retaining nutritional quality. These high oleic lines could be utilized further in breeding programs for improvement of soybean oil quality.

Despite being one of the important characteristics in determining pasta quality in durum wheat (Triticum turgidum ssp. durum), there is no direct report on inheritance of β-carotene concentration. The objectives of this study were to determine the inheritance of β-carotene concentration and the number of genes involved in six crosses of durum. For the cross PDW-233 (P 1 ) × Bhalegaon-4 (P 2 ), F 1 , F 2 , BCP 1 and BCP 2 populations were developed. For all other crosses, only the F 1 and F 2 populations were developed. β-carotene concentration was determined for all populations and parents of each cross grown at Hol, Maharastra, India. The cross PDW-233 × Bhalegaon-4 was also evaluated at Dharwad, Karnataka, India. Low β-carotene concentration was partially dominant in most of the crosses. Broad sense heritability was 67 and 91% at Dharwad and Hol, respectively, for the cross PDW-233 × Bhalegaon-4 and varied from 74 to 93% for the other five crosses indicating the presence of additive gene effects. The frequency distributions of the trait in the F 2 populations were not normal and were skewed towards the lower parent. Segregation of β-carotene concentration in the six F 2 populations indicated that at least two major genes and two or three minor genes with modifying effects govern the trait. Analysis of variance indicated that environment had comparatively little influence on the trait and this should allow for easy selection. The joint scaling test revealed additive × additive, additive × dominance and dominance × dominance epistatic interactions in the cross PDW-233 × Bhalegaon-4.

In Maharashtra, soybean is cultivated on an area of 3.8 M ha with production of 3.07 m ton with second rank in India. However, low productivity of the crop remains a major problem of soybean cultivation, necessitating the need to ascertain the problems faced by soybean growers. Therefore, a study was conducted in the 20 villages of five districts of western Maharashtra. A survey method using personal interview of 100 farmers and focused group discussion with villagers, were used for data collection during the year 2013-14. Study found that labour problems, irrigation facilities, weed management, marketing of produce, pest and disease management were the top five constraints faced by the farmers in soybean cultivation. Shortage of labour and higher wages during peak period (95%) was major labour related constraints faced by farmers. In irrigation, farmers reported lack of irrigation facilities (81%) as major constraints in soybean cultivation. Proper farm mechanization, water conservation measures, short duration drought resistant varieties of soybean, timely supply of institutional credits and training to farmers on improved cultivation practices are important suggested measures to overcome the constraints faced by these farmers, for sustainable and profitable soybean production.

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