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Pre-flowering photoperiod effects on floral initiation, flowering time and yield components of various crops have been well studied, but the post-flowering photoperiod effects on major field crops are not clearly understood. A controlled environment study was carried out using six long-day (LD) crops, flax, sugar beet, broad bean, triticale, wheat, and rapeseed, and seven short-day (SD) crops including Adzuki bean, potato, rice, peanut, mungbean, cotton and corn with a major objective of evaluating the post-flowering photoperiod effects on their reproductive development and yield components. There were significant inter-and intra-specific differences in their response to post-flowering photoperiod treatments. The effects of short days on LD crops were similar to LD effects on SD crops. The post-flowering duration was prolonged by short photoperiod in LD crops and long photoperiod in SD crops. There was, however, significant genotypic variation within a species for such effects. The post-flowering LD treatment caused abscission of flowers and pods and the resumption of vegetative growth in Adzuki bean. The postflowering LD treatment also delayed the shoot senescence of one of the two potato varieties and decreased the number of tubers per plant in both varieties. The LD treatment delayed maturation of rice and mungbean, and decreased seed yield and 100-seed weight of peanut, although the shoot senescence of peanut was not apparently affected. Rapeseed, wheat, cotton and corn genotypes in this study did not show any sensitivity to post-flowering photoperiod. In triticale (an LD crop) exposure to short photoperiod post-flowering increased the number of spikes per plant perhaps due to a greater assimilate accumulation over a longer duration. The results from the current study as well as those from our previous experiments suggest that post-flowering photoperiod responses do exist in diverse field crops, and that there are strong genotypic differences in sensitivity and magnitude of response to post-flowering photoperiod. Photoperiod after flowering substantially regulates the source/sink relationship, and promotes partitioning and accumulation of assimilates to storage organs of crops when it favours the reproductive development of crops.

Basils (Ocimum species) of the mint family Lamiaceae are well known for their multiple uses as culinary, aromatic, and medicinal plants worldwide. Basils are integral components of Asian and Mediterranean cuisine and are also widely used for treating diabetes and cancers. Basil has a limited acceptance as a culinary herb in the United States. The potential exists for development of culinary, medicinal, aromatic, and ornamental basil cultivars for production in the southeastern United States. In a preliminary field trial, 84 accessions belonging to six species of the genus Ocimum were evaluated for agronomic parameters in single-row plots. Wide variations exist between and within species for all agronomic traits studied. The mean percent emergence between species ranged from 60.0% for O. americanum var. americanum to 100.0% for an unknown species from Italy and O. campechianum. The aboveground fresh biomass per plant ranged from 424.0 g for O. sellol to 1450.3 g for the unknown Italian accession. The unknown Italian accession produced more branches per plant and also had the highest root, leaf, stem, and inflorescence fresh and dry weights among species. Ocimumsellol plants emerged late, had a slower rate of emergence, and produced a lower total biomass than other species. Ocimumgratissimum partitioned a greater proportion of the total dry weight to leaves (37.9%) and roots (14.4%), whereas O. basilicum. O americanum var. americanum, and O. campechianum partitioned a greater amount of dry matter to inflorescence and the least to roots than other species. In this presentation, the agronomic traits and basil cultivars with potential for ornamental and medicinal purposes will be discussed.