[Current status and research advances of late spring coldness in wheat]. / å°éº¦å€’æ˜¥å¯’ç ”ç©¶çŽ°çŠ¶ä¸Žè¿›å±•.

Low temperature disasters in wheat occur frequently in recent years, due to global warming. Late spring coldness in wheat during jointing-booting stage is one of the important factors limiting the yield and quality of wheat. Here, we summarized the occurrence characteristics (identification, classification, and space-time characteristics) of late spring coldness in wheat, and the effects of late spring coldness on physiological characteristics (leaf, stem, spike, and root), yield and quality of wheat. Furthermore, we reviewed the research progresses on the breeding of late spring coldness tolerant wheat, molecular biology mechanism, the monitoring, early warning and risk assessment of late spring coldness. Finally, future research work on genetic basis of wheat resistance to late spring coldness, evaluation system for wheat damaged by late spring coldness, prevention and control technology system were prospected to provide a theoretical basis for genetic improvement and new cultivation regulation measures of the resistance of wheat varieties to late spring coldness.

A novel Brassica-rhizotron system to unravel the dynamic changes in root system architecture of oilseed rape under phosphorus deficiency.

BACKGROUND AND AIMS: An important adaptation of plants to phosphorus (P) deficiency is to alter root system architecture (RSA) to increase P acquisition from the soil, but soil-based observations of RSA are technically challenging, especially in mature plants. The aim of this study was to investigate the root development and RSA of oilseed rape (Brassica napus L.) under low and high soil P conditions during an entire growth cycle. METHODS: A new large Brassica-rhizotron system (approx. 118-litre volume) was developed to study the RSA dynamics of B. napus 'Zhongshuang11' in soils, using top-soils supplemented with low P (LP) or high P (HP) for a full plant growth period. Total root length (TRL), root tip number (RTN), root length density (RLD), biomass and seed yield traits were measured. KEY RESULTS: TRL and RTN increased more rapidly in HP than LP plants from seedling to flowering stages. Both traits declined from flowering to silique stages, and then increased slightly in HP plants; in contrast, root senescence was observed in LP plants. RSA parameters measured from the polycarbonate plates were empirically consistent with analyses of excavated roots. Seed yield and shoot dry weights were closely associated positively with root dry weights, TRL, RLD and RTN at both HP and LP. CONCLUSIONS: The Brassica-rhizotron system is an effective method for soil-based root phenotyping across an entire growth cycle. Given that root senescence is likely to occur earlier under low P conditions, crop P deficiency is likely to affect late water and nitrogen uptake, which is critical for efficient resource use and optimal crop yields.