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Increasing rice production is quintessential to the task of sustaining global food security, as a majority of the global population is dependent on rice as its staple dietary cereal. Among the various constraints affecting rice production, reproductive stage drought stress (RSDS) is a major challenge, due to its direct impact on grain yield. Several quantitative trait loci (QTLs) conferring RSDS tolerance have been identified in rice, and qDTY12.1 is one of the major QTLs reported. We report the successful introgression of qDTY12.1 into Pusa 44, a drought sensitive mega rice variety of the northwestern Indian plains. Marker-assisted backcross breeding (MABB) was adopted to transfer qDTY12.1 into Pusa 44 in three backcrosses followed by four generations of pedigree selection, leading to development of improved near isogenic lines (NILs). Having a recurrent parent genome (RPG) recovery ranging from 94.7–98.7%, the improved NILs performed 6.5 times better than Pusa 44 under RSDS, coupled with high yield under normal irrigated conditions. The MABB program has been modified so as to defer background selection until BC3F4 to accelerate generational advancements. Deploying phenotypic selection alone in the early backcross generations could help in the successful recovery of RPG. In addition, the grain quality could be recovered in the improved NILs, leading to superior selections. Owing to their improved adaptation to drought, the release of improved NILs for regions prone to intermittent drought can help enhance rice productivity and production.

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The present study was conducted to develop the effective disinfection protocol for the in vitro micropropagation of strawberry (Fragaria x ananassa Duch) with the use of shoot tips, runner tips, nodal segments and leaf segments as explants. The explants used in this study were surface sterilized using antibiotics, fungicides and other sterilants for different time durations. Although using the same sterilants, the most effective and successive way of using sterilants is different upon the time duration for each sterilant. In this study, two sterilization protocols were used and each protocol included same fungicide and antibiotics concentrations for the same time durations but there were slightly different concentrations and time durations of other sterilants. The present investigation revealed that the most effective way of sterilization protocol which were observed on the nodal segments while treated with protocol II including (10ml/L) fungicide solution for 2 hours, (500mg/L) concentration of ciprofloxacin for 1 hour, (20%) chlorox solution with two drops of Tween 20 for 5 mins, (70%) ethanol solution for 5 mins and (0.1 %) mercuric chloride solution for 4mins. However the same sterilants using the same sterilization time did not give raise the survival rate for runner tip explants, because these treatments resulted in tissue necrosis and contamination and then finally the death of the explant materials. And also, the explants of shoot tips and leaf segments were not shown the effective result compared with using nodal segments. So, for the micropropagation of field grown strawberry, the sterilization protocol II was suite for the nodal segments used as explants for the culture initiation on MS basal medium.