A new cytoplasmic male sterility (CMS) source in Brassica juncea (2n = 36; AABB) was developed by substituting its nucleus into the cytoplasm of Enarthrocarpus lyratus (2n = 20; E(l)E(l)). Male sterility was complete, stable and manifested in either petaloid- or rudimentary-anthers which were devoid of fertile pollen grains. Male sterile plants resembled the euplasmic B. juncea except for slight leaf yellowing and delayed maturity. Leaf yellowing was due mainly to higher level of carotenoids rather than a reduction in chlorophyll pigments. Female fertility in male-sterile plants varied; it was normal in lines having rudimentary anthers but poor in those with petaloid anthers. Each of the 62 evaluated germplasm lines of B. juncea was a functional maintainer of male sterility. The gene(s) for male-fertility restoration ( Rf) were introgressed from the cytoplasm donor species through homoeologous pairing between A and E(l) chromosomes in monosomic addition plants (2n = 18II+1E(l)). The percent pollen fertility of restored F(1) ( lyr CMS x putative restorer) plants ranged from 60 to 80%. This, however, was sufficient to ensure complete seed set upon by bag selfing. The CMS ( lyr) B. juncea compared favourably with the existing CMS systems for various productivity related characteristics. However, the reduced transmission frequency of the Rf gene(s) through pollen grains, which was evident from the sporadic occurrence of male-sterile plants in restored F(1) hybrids, remains a limitation.

A field experiment was conducted for three years under irrigated conditions for productivity enhancement of soybean through integrated nutrient and other agronomic interventions. Application of N, P, K and FYM significantly enhanced the yield of soybean over control. Maximum yield was observed in the treatment where FYM was applied with NPK and resulted in an increase of 15.1 per cent over NPK alone. Application of additional 30 kg N ha -1 at pre-flowering or at pod initiation did not significantly enhance the yield over the basal dose of NP applied at sowing. Application of 4 tonnes wheat straw mulch + 30 kg N +60 kg P 2 O 5 and 30 kg N + 60 kg P 2 O 5 ha -1 showed similar effect on seed yield of soybean. No statistical difference in soybean yield was obtained in the conventional flat and bed sowing treatments. Pre-emergence application of pendimethaline @ 1.5 l ha -1 along with one hand weeding at 40 days after sowing (DAS) and two hand weeding at 20 and 40 DAS were equally effective for weed control and in influencing the soybean yield. The application of N, P, K, FYM, in different treatments, treatment with Bradyrhizobium japonicum and sowing on beds all significantly improved the N, P and K uptake by soybean over control. Application of FYM to soybean resulted in maximum enhancement of nutrient uptake by soybean. After three years a significant improvement in soil OC, available N, P and K was observed in all treatments over control.

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The rice–wheat cropping system (RWCS) has substantially contributed in making India self-sufficient in food grain production; however, rice residue management is of great concern, threatening the sustainability of this system. Rice residue is invariably disposed of by farmers through open burning. In addition to environmental pollution, residue burning of rice also leads to loss of soil nutrients. One of the alternatives to overcome these problems and sustain the RWCS is managing the rice residues in the field itself. Rice residue retention has variable effects on agricultural pests (namely, weeds, insect pests, diseases, and rodents) in the RWCS. High weed infestation in the RWCS results in high consumption of herbicides, which leads to several ecological problems and evolution of herbicide resistance. The shift from intensive tillage to conservation tillage causes major changes in weed dynamics and herbicide efficacy. Incorporation of rice residue reduces weed density and helps in improving soil physical, chemical, and biological properties. Rice residue retention on the surface or mulching reduces weed density and the biomass of both grass and broadleaf weeds in wheat crop as compared to its removal. Long-term field studies involving the use of rice residue as a component of integrated weed management strategies are needed to be done in the RWCS.

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Substituting the nuclear genome of Brassica rapa into the cytoplasmic background of Enarthrocarpus lyratus through backcross substitution helped in developing cytoplasmic male sterility (CMS). Alloplasmic male sterile plants had pale green leaves, small flowers with narrow petals and rudimentary anthers. Female fertility, low initially, improved considerably with advanced backcross generations. Male sterility expression was stable throughout the growing season. Except for EC 339014, all B. rapa accessions (38) evaluated were partial maintainers of the male sterility. Introgression of gene(s) for fertility restoration from the cytoplasm donor species was facilitated by homoeologous pairing between B. rapa and E. lyratus genomes, as was apparent from the very frequent occurrence of a trivalent in the monosomic addition plants (2n ¼ 10 II + 1 I). Backcrossing of fertile monosomic addition plants with B. rapa led to the recovery of male fertile plants possessing the stable euploid chromosome number (2n ¼ 20). These plants restored male fertility in crosses with different (lyr) CMS B. rapa genotypes, confirming the introgression of fertility restorer gene(s) from E. lyratus, the cytoplasm donor species.

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India ranks first both as producer and consumer of pulses. It is also the largest importer of pulses as the total domestic requirement outweighs total production. So, to attain self-sufficiency in terms of pulse production the constraints in cultivation need to be addressed. Pulse production faces a series of constraints which include its inherent physiological limitations. These limitations include lower germination percentage, source limitation, low leaf area development, indeterminate growth habit, C3 photosynthetic apparatus, slow initial dry matter accumulation, limited photosynthesis, hormones inhibitors, decline in nodule activity and diversion of metabolic energy to sinks for protein synthesis. To overcome these limitations simple agronomic techniques such as application of growth hormones are adopted. This paper critically reviews the physiological constraints of pulses and effect of growth regulators to improve these limitations and concomitantly increasing yield.