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1.
Seed storage is a major challenge for smallholder farmers in developing nations. Purdue Improved Crop Storage (PICS) bags effectively control the postharvest insect pests of cowpea and other crops. Farmers, encouraged by this success, have begun to expand the use of PICS bags for storing other crops. Little is known about how sorghum seed, one of these important crops, fares when stored under hermetic conditions. Accordingly, we stored sorghum seed for six months in either airtight containers (PICS bags or sealed plastic bottles) or open ones (woven polypropylene bags and open plastic bottles). Overall, sorghum seed stored in PICS bags and in sealed plastic bottles maintained its initial moisture level, germination rate and seed weight. Porous polypropylene bags and open plastic bottles lost moisture over six months. We conclude that sorghum seed can be safely stored in hermetic containers without any loss of quality for extended periods of time.  相似文献   
2.
Peanut sprout has associated with enhance the content of a nonflavonoids known as resveratrol, which influences a variety of functions including against cancer, cardiovascular and delaying ageing. Peanut from Liaoning province of China was used as a material to accumulate resveratrol during germination. The individual effects of soaking temperature and time as well as germination temperature, time and humidity on resveratrol accumulation in 5 days germinated peanut were investigated. Then, based on Box–Behnken design, interactive effects of the germination parameters were evaluated by response surface methodology. The optimum conditions were as follows: soaking temperature at 35 °C, soaking time at 8 h, germination temperature at 29 °C, germination humidity at 90%, and germination time at 5 day. Under the optimum condition, resveratrol content reached 32.87 μg g?1, which was almost 9.78 times higher than that in the peanut which did not germinate.  相似文献   
3.
激光处理对油松种子活力指数的影响   总被引:12,自引:0,他引:12  
用激光分别处理油松干、湿种子,干种子发芽率与活力指数分别为对照组的 136% 和 167% ,浸水 36h后的湿种子发芽率与活力指数分别为对照组的 137% 和 159% 。  相似文献   
4.
Legumes are the base´s diet in several countries. They hold a high nutritional value, but other properties related to human health are nowadays being studied. The aim of this work was to study the influence of processes (boiling or germination) on the phenolic composition of dark beans (Phaseolus vulgaris L. c.v. Tolosana) and their effect on their antioxidant, neuroprotective and anticancer ability. Phenolic composition of raw and processed dark beans was analysed by HPLC-PAD and HPLC–ESI/MS. The antioxidant activity was evaluated by ORAC. Astrocytes cultures (U-373) have been used to test their neuroprotective effect. Anticancer activities were evaluated on three different cell lines (renal adenocarcinoma (TK-10), breast adenocarcinoma (MCF-7) and melanoma (UACC-62)) by sulphorhodamine B method. Qualitative and quantitative differences in phenolic composition have been observed between raw and processed dark beans that influence the antioxidant activity, mainly for germinated samples which show a decrease of antioxidant capacity. Although every assayed extracts decreased reactive oxygen species release and exhibited cytotoxicity activities on cancer cell lines, raw beans proved to be the most active in neuroprotective and antitumoral effects; this sample is especially rich in phenolic compounds, mainly anthocyanins. This study further demonstrated that phenolic composition of dark beans is related with cooking process and so with their neuroprotective and anticancer activity; cooking of dark beans improves their digestion and absorption at intestinal level, while maintaining its protective ability on oxidative process at cellular level.  相似文献   
5.
In this work, the effect of germination of lupin seeds (Lupinus angustifolius L., c.v. Zapatón) on bioactive phenolic compounds as well as on the antioxidant activity was studied. Phenolic compounds were analysed by HPLC-PAD-ESI/MS. The antioxidant activity was determined by spectrophotometry, evaluating the free radical scavenging activity of the samples. Germination produced significant changes in flavonoids and non-flavonoid phenolic compounds. In the analysed samples, isoflavones, flavones and dihydroflavonols in free and conjugated forms were identified. The results obtained indicate that germination modifies the quantitative and qualitative polyphenolic composition of lupin (Lupinus angustifolius L.) seeds during the different days of the process, with a significant increase of flavonoids. An increase in the antioxidant activity was also observed as a consequence of the process. Germination was shown to be a good process to increase the phenolic content of lupin seeds as well as their antioxidant activity.  相似文献   
6.
Sorghum bicolor is an allelopathic crop that reduces the yield of succeeding crops. We have assessed its effect on the germination, emergence, and seedling growth of Arachis hypogea sown in soil that had had a prior sorghum cropping. A. hypogea was sown on rows and interrows of a previous sorghum crop in 1997 and 1998 in Senegal. Seedling establishment (germination rate and seedling weight) was better between rows than on rows of the previous crop. The highest concentrations of phenolic compounds occurred in the rows in 1998, while contents of row and interrow soils were similar in 1997. Vanillic acid was the main component of the six chemicals found in 1997 soils, whereas the 1998 soil samples contained mainly p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillic, and p-coumaric acids (10 phenolics identified). The germination of peanut seeds in water (control), soil water extracts, and mixtures of pure phenolics (equivalent to those in 1997 and 1998 soil samples) was tested. All extracts inhibited germination compared to controls, but there was no significant difference among treatments, i.e., the inhibition was the same for seeds in soil solutions and those in the respective phenolic mixtures. Similarly, there were no significant differences among the germination rates in soil water extracts of rows and interrows or in the pure phenolic mixtures of rows and interrows. We propose a geometrical sowing pattern for peanuts between the rows of the previous sorghum crop to escape the latter's "allelopathic heritage."  相似文献   
7.
成膜保水剂是一种新型土壤改良剂,通过试验发现:0 2%PAA低浓度的成膜保水剂对大多数作物种子的发芽产生促进作用,可提高作物种子的发芽率;0 2%、0 4%PAA浓度的成膜保水剂对玉米的生长有促进作用。酸碱环境不同成膜保水剂在土壤中的成膜深度不同,酸性越强成膜越浅,而且,具有较好的防渗效果。成膜保水剂对土壤的保水性能有较大改善,尤其对20cm土壤耕层的效果更为明显,田间持水量比对照相对增长达27 5%。生产上应针对不同作物采用不同浓度和pH的成膜保水剂。  相似文献   
8.
烤烟催芽包衣种子试验   总被引:1,自引:0,他引:1  
为了提高包衣种子的发芽率和出苗整齐度,进行了烤烟催芽包衣种子的试验.结果表明,催芽包衣种子较常规包衣种子的发芽势提高了21.7~35.8个百分点、发芽率提高了3.2~9.2个百分点.在大理州烟区催芽包衣种子可提前出苗5~7d,苗期与大田期烟株的生长势和生长整齐度均优于常规包衣种子.  相似文献   
9.
Bacillus cereus is an endospore-forming bacterium able to cause food-associated illness. Different treatment processes are used in the food industry to reduce the number of spores and thereby the potential of foodborne disease. Chitosan is a polysaccharide with well-documented antibacterial activity towards vegetative cells. The activity against bacterial spores, spore germination and subsequent outgrowth and growth (the latter two events hereafter denoted (out)growth), however, is poorly documented. By using six different chitosans with defined macromolecular properties, we evaluated the effect of chitosan on Bacillus cereus spore germination and (out)growth using optical density assays and a dipicolinic acid release assay. (Out)growth was inhibited by chitosan, but germination was not. The action of chitosan was found to be concentration-dependent and also closely related to weight average molecular weight (Mw) and fraction of acetylation (FA) of the biopolymer. Chitosans of low acetylation (FA = 0.01 or 0.16) inhibited (out)growth more effectively than higher acetylated chitosans (FA = 0.48). For the FA = 0.16 chitosans with medium (56.8 kDa) and higher Mw (98.3 kDa), a better (out)growth inhibition was observed compared to low Mw (10.6 kDa) chitosan. The same trend was not evident with chitosans of 0.48 acetylation, where the difference in activity between the low (19.6 kDa) and high Mw (163.0 kDa) chitosans was only minor. In a spore test concentration corresponding to 102-103 CFU/ml (spore numbers relevant to food), less chitosan was needed to suppress (out)growth compared to higher spore numbers (equivalent to 108 CFU/ml), as expected. No major differences in chitosan susceptibility between three different strains of B. cereus were detected. Our results contribute to a better understanding of chitosan activity towards bacterial spore germination and (out)growth.  相似文献   
10.
磁化水对甜菜种子萌发期和幼苗期体内几种酶活性的影响   总被引:6,自引:1,他引:6  
磁化水可提高甜菜种子萌发期和幼苗期体内淀粉酶活性、过氧化氢酶活性、超氧化物歧化酶活性。磁化水可提高甜菜种子的发芽势。  相似文献   
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