Fifteen million farmers in India engaged in Maize cultivation. India would require 45 MMT of Maize by 2022. But, only 15% of cultivated area of maize is under irrigation and water shortage has been a challenge for sustainability of maize production. Water deficit stress (WDS) during pre-flowering and grain filling stages massively affects the plant performance due to imprecise traits function. Thus, the effect of WDS on non-drought tolerant (NDT) and drought tolerant (DT) maize lines were investigated. WDS increased the flowering days, days to maturity, anthesis silk interval, decreased the leaf number, abnormal expression of secondary stress responsive traits, loss of normal root architecture which overall lead to a reduction in GY/ha. WDS at flowering and grain filling stage leads to significant yield penalty especially in NDT lines than DT lines. The yield penalty was ranged from 34.28 to 66.15% in NDT and 38.48 to 55.95% in DT lines due to WDS. Using multiple statistics, traits which improve WDS tolerance in maize were identified viz; number of leaves, number of stomata on lower surface of leaf, leaf angle at ear forming node internodal length between 3 rd and 4 th leaf from top, flag leaf length, flag leaf width, ear per plants, leaf senescence, pollen stainability, root fresh weight and root length. These traits would help in trait specific breeding in maize for WDS tolerance.

Twenty maize genotypes (19 inbred lines and a commercial hybrid) were studied assessing the extent of genetic diversity for 21 qualitative and quantitative morpho-metric traits and 18 expressed sequence tags-simple sequence repeats (EST-SSR) markers. A wide range of variation was observed among the 20 maize genotypes for quantitative traits predominantly for plant height, ear height, days to tasseling, days to silking, and kernel yield per plant. Among the qualitative traits, green-glume base, green internode, conico-cylindrical, flint grain texture, and white stone type were found predominant. The 18 primer pairs produced 92 different markers with polymorphism information content (PIC) value ranging from 0 to 0.87. Three different dendrograms based upon the dis/similarity coefficients were constructed. Poor and no correlations were observed among the sets of dendrograms patterns depicted from qualitative and quantitative traits and molecular markers. However, wide variation among genotypes of different clusters and within clusters was observed for different methods of clustering. It was concluded that the selection of suitable clustering system of genotypes should be determined by the purpose of clustering.

A field experiment was conducted at Rampur, Nepal to see the effect of tillage, residue and nutrient management practices on soil properties and grain yield of rice. Three factors each with two levels i.e. tillage (with or without), residue (with or without) and nutrient management (recommended dose (RD) with 100:60:30 NPK kg ha -1 and farmer's doses (FD) with 5Mt ha -1 of FYM+50:23:0 NPK kg ha -1 . Thus, altogether eight treatment combinations were evaluated under strip-split plot design with three replications. Higher soil organic matter was recorded in residue kept (5.73%) than the residue removed plots. Exchangeable potassium was found higher in no tillage (110.52 kg ha -1 ) than the conventional tillage (76.77 kg ha -1 ). Number of effective tillers was higher in no tillage; residue kept and recommended doses of fertilizer. Grain yield was significantly higher in no tillage with 3.66 Mt and residue kept with 3.72 Mt ha -1 compared to conventional tillage with 2.28 Mt and residue removed plots having 2.22 Mt ha -1 . RD produced significantly higher grain yield of 4.53 Mt ha -1 than FD with 1.41 Mt ha -1 . Therefore, untilled direct seeded rice with residue and recommend does of nutrients seem promising in Terai region of Nepal.

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