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Using CROPGRO-Chickpea model (revised version), we investigated the impacts of climate change on the productivity of chickpea (Cicer arietinum L.) at selected sites in South Asia (Hisar, Indore and Nandhyal in India and Zaloke in Myanmar) and East Africa (Debre Zeit in Ethiopia, Kabete in Kenya and Ukiriguru in Tanzania). We also investigated the potential benefits of incorporating drought and heat tolerance traits in chickpea using the chickpea model and the virtual cultivars approach. As compared to the baseline climate, the climate change by 2050 (including CO2) increased the yield of chickpea by 17% both at Hisar and Indore, 18% at Zaloke, 25% at Debre Zeit and 18% at Kabete; whereas the yields decreased by 16% at Nandhyal and 7% at Ukiriguru. The yield benefit due to increased CO2 by 2050 ranged from 7 to 20% across sites as compared to the yields under current atmospheric CO2 concentration; while the changes in temperature and rainfall had either positive or negative impact on yield at the sites. Yield potential traits (maximum leaf photosynthesis rate, partitioning of daily growth to pods and seed-filling duration each increased by 10%) increased the yield of virtual cultivars up to 12%. Yield benefit due to drought tolerance across sites was up to 22% under both baseline and climate change scenarios. Heat tolerance increased the yield of chickpea up to 9% at Hisar and Indore under baseline climate, and up to 13% at Hisar, Indore, Nandhyal and Ukiriguru under climate change. At other sites (Zaloke, Debre Zeit and Kabete) the incorporation of heat tolerance under climate change had no beneficial effect on yield. Considering varied crop responses to each plant trait across sites, this study was useful in prioritizing the plant traits for location-specific breeding of chickpea cultivars for higher yields under climate change at the selected sites in South Asia and East Africa. 相似文献
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Chilling requirement, together with heat requirement, which has an impact on the climatic distribution of the genotypes of tree species, determines the flowering date. It also played an important role in the protected cultivation of fruit trees. In our study, we estimated chilling requirements for breaking of dormancy and heat requirements for flowering for 2 successive years in 69 Japanese apricot cultivars of Nanjing (China). The chilling requirements of those Japanese apricot cultivars ranged from 24 to 82 chill portions according to the dynamic model, and the heat requirements of those cultivars fluctuated between 691.9 and 2634.7 growing degree hours. The Japanese apricot cultivars were classified into three groups according to their chilling requirements: the low chilling requirement cultivars with less than 50 chill portions, the medium chilling requirement cultivar ranging from 50 to 70 chill portions, and the high chilling requirement cultivars with more than 70 chill portions. In our study, cultivars originated in Guangdong of China generally have a low chilling requirements, and originated in Zhejiang and Jiangsu of China have a high chilling requirements. Cultivars with lower or higher chilling requirement are not suitable for introduction of Nanjing due to their abnormal phenotype. We also observed that the heat requirement of Japanese apricot had no obvious relationship with their origins. The determination of chilling requirements of 69 Japanese apricot cultivars provided some basis for their rationalized introduction and distribution, and was also important in a breeding program. Those results also expanded our understanding of the temperature responses of flower bud in Japanese apricot during the dormancy progress. 相似文献
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Lijuan Ma;Muhammad Fraz Ali;Yulan Ye;Xiaohu Huang;Zili Peng;Muhammad Asad Naseer;Rui Wang;Dong Wang; 《Journal of Agronomy and Crop Science》2024,210(5):e12745
The increase in crop yield can be primarily attributed to the combined effect of genetic advancements, as well as increased contributions from nitrogen (N) and water. The accumulation of dry matter plays a crucial role in determining grain yield in winter wheat. The current study aimed to better understand the source-sink dynamics, analyse the dry matter transport (DMT) before and after anthesis and calculate its ratio to grain yield. In this experiment, eight main cultivars of winter wheat that have been widely cultivated in Shaanxi Province since the 1940s were selected as planting material. Field examinations were conducted using three levels of both irrigation and N. The yield-related parameters, dry matter accumulation, dry matter distribution, DMT and DMT efficiency were measured. The results showed that irrigation prolonged the time of dry matter accumulation, and the application of N fertiliser increased the rate of dry matter accumulation. The analysis of the dynamic characteristic parameters of dry matter in winter wheat showed that irrigation and N had a significant impact on rate of dry matter accumulation. The proportion of stems, leaves and spikes of new varieties increased significantly (p < 0.05), which increased by 56.67%–69.7%, 13.26%–18.07% and 15.78%–28.26%, respectively, with the varietal improvement. The DMT efficiency increased with varietal improvement and also with increased irrigation and N application. The response of irrigation treatment to DMT and dry matter was more significant. In addition, the irrigation treatment had a higher effect on the DMT efficiency of vegetative organs after anthesis. The logistic equation analysis revealed that water stress accelerated the fulfilment of maximum daily temperature (Tmax), while both the maximum growth rate (Gmax) and dry matter weight (Wmax) decreased as water stress increased. There was a positive linear relationship between dry matter accumulation after anthesis and grain yield. The structural equation model showed that varieties, N application and irrigation had significant positive effects on DMT, post-anthesis dry matter and grain yield, while irrigation had significant negative effects on DMT efficiency. The accumulation of dry matter in winter wheat after anthesis showed a significant increase with the succession of varieties. The combination of moderate deficit irrigation and fertilisation improved transportation and dry matter accumulation after anthesis in winter wheat, thereby enhancing its production capacity. 相似文献
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Isatis tinctoria L. (woad) is a dye plant whose cultivation is increasing because of its adaptability to marginal conditions and increasing demand for natural products. Suitable breeding schemes need to be set up in order to obtain woad varieties for each proposed environment. Presently, no data about the reproductive system are available. The effects of selfing and crossing on setting and progeny vigour were assessed. Results showed the existence of an outcrossing system in I. tinctoria. Obligate self-pollinated plants produced fewer siliques (7.1 g per plant) with lower weight (6.0 mg) and lower seed germinability (8.2%) than outcrossing plants (44.1 g, 8.0 mg and 46.0% for each character, respectively). Self-pollinated progenies also generally showed lower vigour than outcrossing progenies. 相似文献
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近年来,我国农业机械的使用量明显增加,为农业生产的顺利开展提供了有力保证,与此同时农机维修服务工作也得到了长足发展,但与农机技术和农机保有量的快速进步相比,基层农机维修能力仍不尽人意,全面提升基层农机维修能力意义重大.农机维修的质量直接关系到农业机械的使用状态,对于农业生产的顺利实施影响很大,为进一步提升我国农业机械化... 相似文献
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青岛梅园的建设及梅花品种的搜集与选育 总被引：1，自引：2，他引：1
在简介青岛梅园这一北方“新星”后,着重报道了其在建园中完成的两项科研成果,即①梅园快速规划设计与施工;②梅花品种的搜集、整理与新品种选育 相似文献
10.
Experiments were conducted with early segregating generations of a selected narrow-leaf lupin cross to determine the effectiveness of selection for yield based on alternative criteria. F2 plants were selected on the basis of seed yield and several other yield-related characters to generate separate F3 populations. Randomly selected plants from each population were grown over the summer (off-season) in a glasshouse to generate F4 populations. Analyses of relationships between F2 plant measurements and F3 progeny mean yields revealed significant correlations only for those characters with the highest heritabilities - flowering time, 100 seed weight and harvest index. However, selection for the earliest flowering F2 plants followed by selection within this group of plants with the highest number of pod bearing branches would result in the greatest increase in F3 mean yield. The F2-derived F4 populations with the highest seed yields were those obtained by selection for total plant dry weight, number of pod bearing branches and number of pods per plant. Improvement in commercial crop yield should therefore be obtained through selection in early generations for those characters contributing to the greatest number of pods per unit area. A scheme involving selection for early flowering and high number of pod bearing branches in the F2 combined with replicated yield tests in the F4 is proposed. 相似文献