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Dong F Yang Z Baldermann S Sato Y Asai T Watanabe N 《Journal of agricultural and food chemistry》2011,59(24):13131-13135
As a defense response to attacks by herbivores such as the smaller tea tortrix ( Adoxophyes honmai Yasuda), tea ( Camellia sinensis ) leaves emit numerous volatiles such as (Z)-3-hexen-1-ol, linalool, α-farnesene, benzyl nitrile, indole, nerolidol, and ocimenes in higher concentration. Attack of Kanzawa spider mites ( Tetranychus kanzawai Kishida), another major pest insect of tea crops, induced the emission of α-farnesene and ocimenes from tea leaves. The exogenous application of jasmonic acid to tea leaves induced a volatile blend that was similar, although not identical, to that induced by the smaller tea tortrix. Most of these herbivore-induced plant volatiles (HIPV) were not stored in the tea leaves but emitted after the herbivore attack. Both the adaxial and abaxial epidermal layers of tea leaves emitted blends of similar composition. Furthermore, HIPV such as α-farnesene were emitted mostly from damaged but not from undamaged leaf regions. A principal component analysis of metabolites (m/z 70-1000) in undamaged tea leaves exposed or not to HIPV suggests that external signaling via HIPV may lead to more drastic changes in the metabolite spectrum of tea leaves than internal signaling via vascular connections, although total catechin contents were slightly but not significantly increased in the external signaling via HIPV. 相似文献
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以抗旱性差异显著的两种苹果砧木楸子(Malus prunifolia)和平邑甜茶(Malus hupehensis Reld)为材料,研究了干旱胁迫对两种砧木根和叶中脱落酸(ABA)、生长素(IAA)、赤霉素(GAs)和玉米素核苷(ZR)含量的影响.结果表明:干旱胁迫下,与非抗旱砧木平邑甜茶相比,抗旱砧木楸子中抑制生长... 相似文献
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Feeding different dietary protein to energy ratios to Holstein heifers: effects on growth performance,blood metabolites and rumen fermentation parameters 下载免费PDF全文
L. F. Dong W. B. Zhang N. F. Zhang Y. Tu Q. Y. Diao 《Journal of animal physiology and animal nutrition》2017,101(1):30-37
Eighteen Chinese Holstein heifers average age 230 ± 14 days were allocated to 1 of 3 dietary crude protein (CP) to metabolizable energy (ME) ratios to examine the effects on growth performance, blood metabolites and rumen fermentation parameters with 90‐days experiment. Three different dietary CP:ME ratios were targeted based on the formulation of dietary CP contents of 10.85%, 12.78% and 14.63% on dry matter (DM) basis with similar ME contents (10.42 MJ/kg DM), which were categorized as low, medium and high dietary CP:ME ratios. The actual CP:ME ratios obtained in this study significantly increased from low to high CP:ME ratio groups with a value of 10.59, 11.83 and 13.38 g/MJ respectively. Elevated CP:ME ratios significantly increased CP intake (kg/day) and feed efficiency (FE) which was defined as dry matter intake as a proportion of average daily gain (ADG), whereas little difference was observed in body weight (kg), ADG (kg/day), DM intake (kg/day) and ME intake (MJ/day) among the three different CP:ME ratio groups. Increasing dietary CP to ME ratios significantly increased CP digestibility, whereas digestibility of DM and gross energy remained constant in the current experiment. Blood urea nitrogen and insulin‐like growth factor‐1 linearly increased with increasing dietary CP:ME ratios. There was significantly dietary treatment effect on rumen fermentation parameters including acetate, propionate, butyrate and total volatile fatty acids. Therefore, this study indicated that increasing dietary CP levels with similar energy content contributed to increased protein intake and its digestibility, as well as FE. Holstein heifers between 200 and 341 kg subjected to 13.38 dietary CP:ME ratio showed improved feed efficiency, nutrient digestibility, some blood metabolites and rumen fermentation characteristics for 0.90 kg/day rate of gain. 相似文献