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Drought limits the growth and development of Phaseolus vulgaris L. (known as common bean). Common bean plants contain various phenylpropanoids, but it is not known whether the levels of these metabolites are altered by drought. Here, BT6 and BT44, two white bean recombinant inbred lines (RILs), were cultivated under severe drought. Their respective growth and phenylpropanoid profiles were compared to those of well-irrigated plants. Both RILs accumulated much less biomass in their vegetative parts with severe drought, which was associated with more phaseollin and phaseollinisoflavan in their roots relative to well-irrigated plants. A sustained accumulation of coumestrol was evident in BT44 roots with drought. Transient alterations in the leaf profiles of various phenolic acids occurred in drought-stressed BT6 and BT44 plants, including the respective accumulation of two separate caftaric acid isomers and coutaric acid (isomer 1) relative to well-irrigated plants. A sustained rise in fertaric acid was observed in BT44 with drought stress, whereas the greater amount relative to well-watered plants was transient in BT6. Apart from kaempferol diglucoside (isomer 2), the concentrations of most leaf flavonol glycosides were not altered with drought. Overall, fine tuning of leaf and root phenylpropanoid profiles occurs in white bean plants subjected to severe drought. [ABSTRACT FROM AUTHOR]

Aims: In Ontario, Canada, acreage of red clover (Trifolium pratense L.) intercropped with winter wheat (Triticum aestivum L. em. Thell) has declined, despite well-documented soil and yield benefits. The decline has resulted from increasing prevalence of stand non-uniformity, which has been attributed in part to soil moisture deficits. We examined whether there are genotypic differences in drought response between red clover varieties.Methods: A double-cut (Belle) and a single-cut variety (Altaswede) were grown under four different durations of drought (4, 8, 12 and 16 days below 15% relative soil water content, RSWC). Shoot dry weight, shoot relative water content (RWC), leaf area and crown water content were measured in control, drought and drought + recovery treatments.Results: Belle used significantly more water during soil moisture deficit and had greater leaf area, shoot dry weight and RWC compared to Altaswede. In contrast, Altaswede had significantly higher survival rates than Belle, attributed to maintenance of meristematic tissue viability in the crown where re-growth, after shoot tissue desiccation, can occur.Conclusions: By demonstrating genotypic variation in survival strategies of red clover, traits can be identified for the development of improved varieties. Varieties with higher survival rates during drought will result in more uniform stands and increased utilization of red clover for environmental and yield benefits. [ABSTRACT FROM AUTHOR]

Highlights • Water deficit and nematode infection negatively affected seedcotton yield. • Increased water availability did not offset nematode-induced yield loss. • Yield loss was associated with declines in boll density not boll mass. • Boll distribution patterns were similar for both stresses. • Drought most negatively affected boll retention at positions further from the mainstem. Abstract Both root-knot nematode (RKN) infection and water deficit negatively affect yields in many cotton growing regions of the southern United States. The objective of the current study was to determine whether seedcotton yield limitations due to drought and RKN infection were brought about through similar effects on yield components and boll distribution patterns. To this end, yield component and boll distribution assessments were conducted for a seven-year study in Tifton, Georgia that included three irrigation treatments and two fumigant treatments to manage nematodes. Seedcotton yield was strongly affected by year, irrigation treatment and fumigant treatment, but no interactions were observed between the two factors, illustrating that the yield limiting effects of nematode infection could not be mitigated by providing a water-replete condition. Yield declines due to nematode infection and water deficit were primarily driven by a decline in total boll density. Yield distribution patterns revealed that water deficit negatively affected boll numbers for all branch types and at all positions along a fruiting; furthermore, the mainstem node of peak boll distribution was lower under drought. The trend was similar for nematode infected plants (except that boll density at position two was not affected by fumigation and retention at position three increased slightly). One notable difference between drought and nematode effects was that the relative decline in boll density for drought-stressed plants was greater at sympodial positions further from the mainstem, but this was not the case due to nematode infection. [ABSTRACT FROM AUTHOR]