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干旱缺水是导致果园低产、低效的主要原因之一。重庆三峡库区降水丰沛,但水资源在时空上分布很不均匀,许多坡地果园水源紧缺,季节性干旱十分突出。2002年7月至2006年1月,通过用叶片水分亏缺与果实膨大相关性的研究以及水分管理模式,对柑橘生长和发育的影响进行试验研究,总结出了一套适合坡地柑橘园的水分管理模式。 相似文献
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枇杷果实采后质地的变化与调控 总被引:7,自引:1,他引:7
以枇杷果实为材料, 通过1 - 甲基环丙烯(1-MCP) 和温度处理, 探索其对采后枇杷果实衰老过程质地的影响。结果表明, 枇杷果实采后在20℃贮藏过程中, 脂氧合酶(LOX) 活性、超氧自由基(O·2 ) 积累和苯丙氨酸解氨酶( PAL) 活性均呈峰型变化, 果肉组织相对电导率持续增加, 果实硬度趋于增大, 果肉渐趋粗糙少汁, 具有组织木质化的特征。12MCP可以显著抑制PAL和LOX活性, 减缓O·2 生成, 延缓组织衰老进程和硬度的增加。1℃低温贮藏可以有效延缓果实的衰老进程, 但会导致果实出现冷害, 其典型症状也表现出了组织木质化。采后枇杷果实衰老过程中的硬度增加与冷害胁迫下的果实组织木质化具有相似的基本特征, 但其内在机制可能不同。 相似文献
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The effects of root colonization by the arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck and Smith on growth, flower and fruit production, and fruit quality were studied in field-grown tomato plants exposed to varying intensities of drought stress. Inoculated (M+) and non-inoculated (M−) tomato seedlings were exposed to varying intensities of drought stress by adjusting irrigation intervals. Mycorrhizal plants had significantly higher uptake of N and P in both roots and shoots regardless of intensities of drought stress. AM inoculation also significantly increased shoot dry matter and the number of flowers and fruits. The fruit yields of M+ plants under severe, moderate, mild drought-stressed conditions were higher than M− plants by 24.7%, 23.1%, 16.2% and 12.3%, respectively. Furthermore, M+ plants produced tomato fruits that contain significantly higher quantities of ascorbic acid and total soluble solids (TSS) than M− plants. Mycorrhizal effects increased with increasing intensity of drought. The overall results suggest that mycorrhizal colonization affects host plant nutritional status, water stratus and growth under field conditions and thereby alters reproductive behaviour, fruit production and quality of fruits under both well-watered and drought-stressed conditions. 相似文献
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Due to the several advantages expected from growing self-compatible almond cultivars, breeding programmes have recently introduced self-compatibility as an important trait. However, doubts have arisen regarding the capability of the newly obtained self-compatible almonds to produce good yields in monovarietal plantations, and the commercial quality of the fruits from self-pollination. For this reason, in the last years several studies have been conducted to evaluate fruit set and fruit traits following self- and cross-pollination of self-compatible almonds. Their results showed inconsistencies for fruit set and for some of the fruit traits studied. Thus, while some studies showed no differences between both pollination types for any of the fruit traits, others clearly showed important differences with the detriment of self-pollination for commercially important fruit traits. The fact that some of these studies evaluated a low number of individuals and/or fruit traits, implies the need of a more complete study. In this work, 10 fruit traits were studied in 26 self-compatible almonds following self-pollination by bagging and open pollination treatments. In general, and despite a few individuals showed differences between both pollination types for two of the traits, the results showed no influence of self-pollination in fruit quality. 相似文献