Ontogenic Changes in Growth and Assimilate Distribution as Influenced by N Supply in Rapeseed-mustard

Brassica juncea , cv. Pusa Bold, and Brassica campestris , cv. Pusa Kalyani, were raised under field conditions with varying levels of N fertilization, i.e. 0, 40, 80 and 120 kg N ha⁻¹. Changes in dry matter accumulation in various plant parts as influenced by N supply were measured throughout the crop ontogeny. N supply up to 120 kg had an increasing effect on the growth of leaves, stem and pods during the entire period till maturity. Analysis on the assimilate distribution pattern revealed that 84–87% of the total was accumulated during the post-flowering phase. Dry matter partitioning profile during the ontogeny indicated that about 72–83 % of the total DM was accumulated in the leaves, while 17–28 % in the stem, in the preflowering phase. This trend was found nearly opposite during the postflowering phase. At maturity, however, stem and pods accounted for nearly equal amounts of dry matter accumulation. Among the genotypes, Pusa Bold recorded significantly higher DM accumulation and seed yield over Pusa Kalyani which, on the other hand, exhibited a better assimilate-partioning ability than the former. Nitrogen levels had a favourable effect on LAI, LAD and CGR in both genotypes. Highly significant correlations were obtained between seed yield vs. LAI, LAD and CGR. N fertilization up to 120 kg ha⁻¹ was found beneficial in enhancing growth and yield of rapeseed-mustard.     

Seed Yield and Yield Contributing Characters as Influenced by N Supply in Rapeseed-mustard

Brasisca Juncea , cv. Pusa Bold, and B. campestris , cv. Pusa Kalyani, were raised under field conditions with varying levels of N supply from 0–120 kg ha^-1. The production profile of branches and pods thereon was measured, per unit area basis, throughout the crop ontogeny. At maturity, data on the yield contributing characters, viz. pod dry weight, pod number, seed number per pod, 1000 seed weight, seed wall ratio and seed yield in different order branches, was recorded.
The branching pattern and the number of pods produced on different order branches, in the two species, was favourably modified by the increasing levels of N supply. Primary and secondary branches contributed to the seed yield to an extent of 80 % of the total yield. Nitrogen treatment had no significant effect on 1000 seed weight. B. juncea exhibited significantly higher yield over B. campestris. N supply up to 120 kg ha ^-1 linearly increased seed yield in both the species. However, it exerted a negative effect too partitioning of assimilates from pod wall to seed. The study indicated that rapeseed-mustard, grown under short winter-season environment with adequate soil moisture, has the potential for higher N-fertilizer optima exceeding 120 kg ha ^-1.     

Design and implementation of agriculture research digital photo manager

Software tools for photo collection management are proliferating, but they are generally developed for personnel photo management and have limited searching and browsing functions. We implemented the Agriculture Research Digital Photo Manager (ARDPM) prototype to enable researchers, extension personnel and other users to efficiently manage, search and browse their research photo archives. Research Digital Photo Manager provides a set of visual Boolean query interfaces for multiple ways of organizing and viewing the same photo collection. It gives users powerful search capabilities. Using thumbnail display and an easy interface, ARDPM is designed to provide users powerful searching and browsing photo capabilities.     

Sulphur Requirement of Rapeseed-Mustard, Groundnut and Wheat: A Comparative Assessment

Two oilseed species, rapeseed-mustard and groundnut, and wheat, a cereal, were compared for their sulphur requirement. Sulphur accumulation pattern in different plant parts at various growth stages indicated a several fold higher requirement of S in rapeseed-mustard as compared to the other two species. A low N: S ratio found in rapeseed-mustard was also an indicative of its higher S requirement. The S requirement of groundnut was found to be similar to that of wheat. The additional S required by rapeseed-mustard may be attributed to the presence of glucosinolates, a characteristic of cruciferous plants. Sulphur fertilization enhanced yield of the oilseed species but not the per cent oil. The role of sulphur in oil biosynthesis is discussed.