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131.
《Plant Production Science》2013,16(3):184-189
AbstractCassava (Manihot esculenta Crantz) can produce a high crop yield even in an environment with irregular rains. This is mainly attributed to its abilities to maintain leaf area under drought conditions and rapidly regrow after rain. In this study, we investigated the mechanism of leaf maintenance under water deficits through measurement of photosynthetic rate and water potential changes in leaves. The cassava plants were grown in pots and exposed to water deficits, and the diurnal changes in water potentials, rates of photosynthesis and transpiration and stomatal conductance were measured. The relationship between leaf water potential (ψW) and photosynthetic rate with decreasing soil water, and osmotic adjustment were also investigated. With respect to water supply in leaves, the movement of water in plants was measured using stem heat balance. Under water deficits, photosynthesis occurred only in the early morning. The water loss was reduced by stomatal closure in the mid-day. This was attributed to the complete closure of the stornata during the decrease in ψW to a range between –1.0 and –1.4 MPa. Furthermore, the firm stomatal closure is caused by the consistency of osmotic potential under decreases in soil water, i.e., to a lack of osmotic adjustment. Water stored in the pith parenchyma of stem flowed into leaves in the morning. From these results, we conclude that cassava can consistently maintain an adequate water level in leaves via water storage and the sensitivity of stornata to water deficits, thereby avoiding leaf dehydration. 相似文献
132.
Anita Sós-Hegedűs Donatas Žvingila Zsófia Bánfalvi Géza Dallmann 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(4):435-439
In this study, cDNAs of two Erwinia carotovora-induced potato genes, designated Solanum tuberosum–Erwinia-induced-1 and 2 (Stei1 and Stei2) were isolated by differential display technique. Stei1 and Stei2 were detected in low copy number in the potato genome and found to encode putative proteins with no significant homology to any genes with known function. Treatment of the leaves with salicylic acid, methyl jasmonate and ethylene elevated neither Stei1 nor Stei2 mRNA levels. However, Stei1 and Stei2 expression were induced not only by E. carotovora but also by infiltration of water in leaves, albeit to a lesser extent. In addition, Stei2 was up-regulated by NaCl, wounding, dehydration and abscisic acid. Thus Stei1 and Stei2 define novel genes belonging to the family of those pathogenesis-related genes whose expression can be induced both by biotic and abiotic stresses. 相似文献
133.
Inhibitory influence of inorganic salts on banana postharvest pathogens and preliminary application to control crown rot 总被引:4,自引:0,他引:4
Dionisio G.?Alvindia Takao?Kobayashi Keiko T.?NatsuakiEmail author Seinosuke?Tanda 《Journal of General Plant Pathology》2004,70(1):61-65
Lasiodiplodia theobromae, Thielaviopsis paradoxa, Colletotrichum musae, C. gloeosporioides, Fusarium verticillioides, and F. oxysporum were screened in vitro for sensitivity to Na2CO3, NaHCO3, CaCl2, NaCl, and NaClO. The spore germination of all pathogens was completely inhibited by Na2CO3 4g/l, NaClO 5g/l, and NaHCO3, CaCl2, and NaCl 6g/l each. Dipping the bananas for 10–15min in these concentrations reduced the incidence of crown rot (compared with the untreated fruits) 17 days after harvest in fruits treated with NaClO by 67%, with NaHCO3 by 62%, with NaCl by 38%, and with CaCl2 by 33%. Na2CO3-treated fruits had the same incidence of crown rot as untreated fruits. 相似文献
134.
热水和1-MCP处理对杧果贮藏效果的影响 总被引:3,自引:2,他引:3
研究了常温下热处理、1-MCP处理及热处理结合1-MCP处理对杜果果实贮藏效果的影响。结果表明:热处理能有效控制杧果采后炭疽病的发生,改善果实外观,提高好果率,延长贮藏时间,但使呼吸增强,不能抑制果实后熟和减少果实失重率;1-MCP处理能降低果实在贮藏过程中的呼吸强度,抑制果实的后熟,减少果实失重率,但对炭疽病的防治无效;热处理结合1-MCP处理在一定程度上结合了2者的优点,该处理既有效的控制了炭疽病的发生,又延缓了杧果果实的后熟进程,延长了贮藏时间,且对杧果果实的品质无不良影响。所有处理对成熟时的可溶性固形物含量、可滴定酸含量及糖酸比无影响,且对蒂腐病的防治效果也均不理想。 相似文献
135.
136.
优质烟叶干物质含量高,在烘烤中常常出现质量问题。采用温度白控烤箱进行试验研究,找出烟叶在烘烤中产生汗烫、烤红、挂灰问题的原因在于:烟叶所需温度没有达到要求时,烟叶就会挂灰;而超过烟叶需要的温度时,烟叶就会发生汗烫现‰解决问题的方法是:在叶片叶色充分变黄之前,脱水率应保持在30%~40%,50%是烟叶在充分变黄时的脱水极限;烟叶进入定色期时,叶片的脱水率一般应不低于鲜烟叶含水饱和质量的30%,如果没达到这一标准,温度就不能超过48℃。 相似文献
137.
138.
利用HSMD-10型烘干箱进行萝卜丝干燥试验,探讨热风温度、热风流量对干燥性能的影响.结果表明,萝卜丝干燥具有典型物料干燥的升温、等速、降速3个阶段,温度和流量对干燥效果的影响显著. 相似文献
139.
SUMMARY: Japanese common squid meat was heat-treated at 80°C for 1 min, cured with 1.0 M sorbitol solution (pH 7.0) at 4°C for 18 h, and dried further at 30°C (60% relative humidity) for 16 h. Osmotic dehydration during the sorbitol curing process and slow moisture vaporization at the initial drying period were observed regardless of the heat denaturation of muscle protein. Simultaneously, lowering the amount of moisture vaporized in the falling rate of the drying period caused a shortening of the total drying time. Furthermore, the shear force of the dried product from heat-treated meat was kept at a lower value by sorbitol curing, although the suppression effect of sorbitol on the hardening of dried meat was lost by protein denaturation. These results are useful for understanding the role of sorbitol in reducing drying time and in eliminating excess hardening of dried squid products. 相似文献
140.