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101.
为了解穗发芽不同程度下对不同筋性春小麦品种品质的影响,该实验选取强筋小麦品种克春1号、克丰6号,中筋品种克旱16、克旱21,弱筋小麦品种新克旱9、克丰9为实验材料,利用人工智能气候培养箱模拟自然环境,人为控制种子发芽程度并测定相关数据,结果表明:出粉率在萌动状态下,强筋>中筋>弱筋,随着发芽程度的加深,出粉率并未表现出与小麦筋性相关的规律性;强筋粉降落值在萌动状态下,较正常状态下降幅度大于中筋粉,中筋粉大于弱筋粉;各筋性小麦品种其湿面筋含量、干面筋含量以及面筋指数均随发芽程度的加深,而降低。 相似文献
102.
艾叶最佳采收时间及水法提取总黄酮工艺研究 总被引:1,自引:0,他引:1
[目的]确定艾叶的最佳采收时间,探讨水法提取总黄酮的最佳工艺条件。[方法]以采自河南省洛宁县的艾叶为材料,用水为提取剂对艾叶中的黄酮进行提取,采用三氯化铝比色法测定样品水提液的总黄酮含量,研究料液比、样品粒度、浸提温度及浸提时间对总黄酮浸出率的影响,通过正交试验确定艾叶中总黄酮的最佳提取工艺,并采用该工艺对不同时间采收的艾叶进行总黄酮提取量的测定。[结果]提取艾叶中总黄酮的最佳工艺是:料液比为1:25,浸提温度为90℃,浸提时间为30min;样品粒度为80目。经对不同时间采收的艾叶中总黄酮提取量的测定,确定艾叶的最佳采收时间为每年的8月份。[结论]用水提取艾叶总黄酮,操作简单,方便快速,是一种比较理想的提取方法。 相似文献
103.
104.
高Vc含量野生蔬菜资源筛选与不同采收期Vc变化 总被引:1,自引:0,他引:1
以福建省28份野生蔬菜为材料,采用钼蓝比色法测定Vc含量,筛选出一些适合江苏省种植的高Vc含量的野菜资源,推荐作为规模化生产使用。选择南京地区长期食用的4种野生蔬菜,研究不同采收期Vc含量的动态变化。结果表明:(1)28种野生蔬菜Vc含量的变幅为6.78~173.25 mg.hg-1。优选出9份高Vc含量的野生蔬菜,为菊花脑、美国碎叶苦苣、人参菜、黄秋葵、枸杞、蕨菜、苦菜1号、蒲公英、洋芥蓝,可以作为南京地区品质较好的野菜食用。(2)不同生长期4种野菜Vc含量均表现为双峰曲线,但最大峰值出现的时间在材料间有差异。宽韭采收期间Vc含量的变化为53.52~196.87 mg.hg-1;荠菜、马兰2号和菜用莴苣Vc含量变化范围相差不大,分别为19.33~118.21 mg.hg-1、39.89~120.90 mg.hg-1和29.93~117.94 mg.hg-1。宽韭和马兰2号最佳采收期为4月中下旬至5月中下旬,荠菜和菜用莴苣为4月中下旬至5月中旬。 相似文献
105.
106.
[目的]针对建平地区烟叶生产雇工难、雇工贵、用工“野蛮操作”导致烟叶机械损伤严重等问题,对其采收运输机械的研究。[方法]通过合理设计烟田部分垄距增加小型农机进地的可能性,采后烟叶放置于专门的编织袋中,运输工使用改进电动三轮车进烟田运烟,然后用安装有专用运输架的运输车运回烤房进行编烟,编烟后放置于专门挂烟架上,全部编完后装到烤房内。[结果]机械的使用大幅降低了烟叶的机械损伤,显著提高了烟叶等级质量,降低了烟叶采收的劳动强度,大幅缩短了采烟全程时间。[结论]减少人为机械损伤,实现提质增效目标,为烤烟采收环节优化提供参考。 相似文献
107.
为调查收割至青贮装填前乳酸菌的动态变化,本研究以甜玉米(Zea mays L.)和热研四号(Pennisetum purpureum×P.americanum‘Reyan No.4’)王草为材料,检测从刈割、切短、放置8h和放置24h四个阶段乳酸菌的动态变化。研究结果表明:从未切短(4.25lg cfu·g~(-1) FM)到切短(5.69lg cfu·g~(-1) FM)阶段乳酸菌的数量显著增加(P0.05),主要是乳酸乳球菌(Lactococcus lactic)、柠檬明串珠菌(Leuconostoc citreum)和融合魏斯氏菌(Weissella confuse)。随着放置时间的延长,乳酸菌种类变化随植物品种而异,甜玉米切短后发现柠檬明串珠菌,放置24h后发现假肠膜明串珠菌(Leuconostoc pseudomesenteroides),而热研四号王草切短后菌株短乳杆菌(Lactobacillus brevis)消失。 相似文献
108.
Determining the optimal selective harvest strategy for mixed-species stands with a transition matrix growth model 总被引:2,自引:0,他引:2
An optimization model was developed to determine the optimal harvesting strategy needed for uneven-aged mixed-species stands in the Changbai Mountain region of northeast of China. The model takes into account four variables including residual basal area (RBA), the diameter of the largest tree, harvest cycle and a constant representing the ratio of the number of trees in a given diameter class to those in the next larger diameter class (‘q’). According to model simulations, under the objective of maximizing net revenue, the optimal harvesting strategy is defined when the residual basal area equals to 19 m2 ha−1, the diameter of the largest tree equals to 44 cm, q 1.3 and the harvest cycle equals to 20 years. If the objective is to maximize the total volume yield, the optimal harvesting strategy is defined when RBA equals to 13 m2 ha−1, the diameter of the largest tree equals to 36 cm and the constant ‘q’ equals to 1.9 and the harvest cycle equals to 15 years. 相似文献
109.
Research and development of an innovative production system for hemp (Cannabis sativa L.) fibre for textile use requires the integration of multidisciplinary knowledge from cultivation technique to realization of end products. Research was carried out to study the effect of the agronomic factors cultivation year (2003–2004), genotype (Futura 75 and Tiborszallasi), plant population (120, 240 and 360 plants m−2) and harvesting time (beginning and full flowering) on fibre yield and quality in the whole hemp stem, and in the basal and apical stem portions separately. The study of separate stem portions was done to determine the effect on fibre quality of an innovative harvesting and processing system in which hemp stems are cut in two portions of approximately 1 m at harvest to enable processing on modern flax scutching lines. 相似文献
110.
Terry J. Rose Juan Pariasca-Tanaka Michael T. Rose Yoshimichi Fukuta Matthias Wissuwa 《Field Crops Research》2010
Continual removal of phosphorus (P) from fields in rice grains at harvest results in lower soil fertility in low-input farming systems and drives the need for fertiliser inputs in high-input farming systems. High-P content in rice grains (the majority as phytate) contributes little to human nutrition and agronomic practices such as growing seedlings in high-P media or seed P coating at sowing (in direct-sown crops) may overcome the reported need for high-P seed for seedling establishment. Thus, reducing the amount of P in rice grains at maturity through breeding may represent a novel means to reduce ‘mining’ of soil P. We investigated the uptake and partitioning of P in rice plants and examined the scope for breeding rice with lower grain P by assessing genotypic variation for phosphorus harvest index (PHI) and seed P concentrations among a set of 38 rice genotypes in the field. At maturity approximately 75% of total plant P was found in grains and translocation of P from stems and leaves contributed substantially to grain P. However, unlike other cereals such as wheat, rice plants continued dry matter and P accumulation until maturity with approximately 40% of total plant P taken up post anthesis. In the field study, PHI differed significantly among genotypes (from 57 to 87) but was highly correlated to HI (P ≤ 0.001), suggesting that exploiting genotypic variation for this trait may be counterproductive. Grain P concentrations varied from 1.96 to 3.18 mg P g−1, and were neither associated with reductions in grain yield or seed size, nor significantly correlated to HI. Grain P concentration therefore appears to be a suitable screening criterion and the 50% variation observed among genotypes suggests that scope exists for breeding rice with lower grain P concentration to reduce the off-take of P from rice fields at harvest. 相似文献