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991.
[Objective] This study was conducted to investigate the effects of light quality on growth and quality of Chinese kale(Brassica alboglabra Bailey). [Method]Chinese kale was grown in hydroponic under three different Light Emitting Diode(LEDs) conditions [red∶blue=8∶1(8R1B), red∶blue=6∶3(6R3B) and red∶green∶blue=6∶2∶1(6R2G1B), 12 h light, 50 μmol/(m2·s)]. Then its growth and quality indices including root and shoot fresh weight and dry weight, concentrations of soluble protein, vitamin C, nitrate, soluble phenols, flavonoids, soluble sugar, free amino acids, and activity of nitrate reductase were measured. [Result] There was no significant difference in plant height, diameter of flower stalk and leaf number among three LED treatments. The fresh weight of shoot, root and plant in 8R1 B and 6R2G1 B was significantly higher than in 6R3 B. The dry weight of shoot and plant in 8R1 B was significantly higher than in 6R3 B. The concentrations of vitamin C, soluble protein and soluble sugar in flower stalk of 6R3 B treatment were significantly higher than those in 8R1 B and 6R2G1 B, while there was no remarkable difference in concentrations of reducing sugar, soluble phenol, flavonoids and free amino acid among the three treatments. The nitrate concentration in flower stalk of 6R3 B was significantly lower than in the other two treatments, and the activity of nitrate reductase in6R3 B was significantly higher than in the other two treatments. [Conclusion] The LED treatment of red:blue=6:3 was more suitable for the growth of Chinese kale. 相似文献
992.
993.
Summary The application of salts including aluminium chloride, potassium sorbate, sodium benzoate and sodium metabisulfite has been
shown to control diseases of stored potato tubers. In order to integrate salt application in the disease control strategies,
it is imperative to evaluate their effect on the quality of stored tubers. The effect of salt application either alone (0.05
M and 0.2 M) or in combination on quality attributes of tubers of two cultivars (Norland and Shepody) stored at 4 °C for up
to 6 months was evaluated. Higher weight losses were generally observed in tubers treated with aluminium chloride and sodium
metabisulfite after 6 months of storage, while the organic salts, sodium benzoate and potassium sorbate, exhibited weight
losses comparable to that of the control tubers. Both organic salts at a concentration of 0.2 M decreased sprout growth on
Shepody cultivar tubers. Sodium benzoate was shown to increase the sugar content of the stored tubers. 相似文献
994.
In the absence of serious post-anthesis stress, the potential supply of assimilates for grain filling in barley appears to exceed the storage (sink) capacity of the grains. The sink capacity is a function of the number of grains per unit land area and their potential size. In order to investigate the contribution of pre and early post-anthesis factors in the control of potential grain weight, regression analysis has been used to analyse data from field experiments conducted on winter barley crops cv. Pearl grown at six sites across the UK between 2002 and 2004. Crops were grown under a comparable husbandry regime with a full crop protection, growth regulator and fertilizer programme. The mean grain weight (MGW) varied from 35 to 46 mg at 100% dry matter over 17 site/year combinations. The variation in MGW between site/years was associated with differences in the rate rather than the duration of grain filling. MGW did not relate well to any measure of above ground growth or crop structure at ear emergence (Zadoks GS59). There was a significant positive linear relationship between MGW and the amount of radiation (PAR) intercepted per unit grain number between ear emergence and the start of rapid grain filling (r2 = 0.32, P = 0.023), but not over the whole grain filling period. This is consistent with the view that MGW is determined by potential grain size. A multiple regression model comprising five explanatory variables accounted for a much larger proportion of the total variation in MGW (r2 = 0.72, P = 0.013) than PAR interception on its own. There were significant positive associations of MGW with post-anthesis radiation use efficiency and PAR intercepted from GS59 to the start of rapid grain growth (RGG), and significant negative associations with the shoot number per plant, mean air temperature from GS39–59 and mean daily rainfall from GS59-RGG. The results suggest that both pre and post-anthesis conditions operate in concert to determine the potential grain weight of barley in temperate climates. The dry weight and water content of grains and ears followed a common pattern during grain growth for all site/years when the percentage moisture content was used as an index to normalise different rates of development. Use of the above data for predicting potential grain weight of barley prior to harvest is discussed. 相似文献
995.
Shlomo Marco 《Potato Research》1984,27(2):155-162
Summary In field trials simulating commercial conditions, secondary PLRV infection of autumn-grown potato crops in Israel significantly
reduced yield, although symptoms were not perceptible. Plots containing 7.3% PLRV-infected seed showed an increase in yield
per plant of 17%, compared with plots with 36.2% infected seed; in plots with only 1.3% infected seed the increase of yield
was 21%. In a second experiment, where individual plants were assayed, the yield of PLRV-infected plants of cv. Blanka was
only 68.7% of that of PLRV-free plants; corresponding figures for cv. Up-to-Date and Désirée were 79.2 and 58% respectively.
PLRV infection was not associated with reduced emergence or with the yield of deformed tubers.
Zusammenfassung W?hrend der ersten zwei Monate der im Herbst liegenden Wachstumszeit der Kartoffel (August-Januar) sind in Israel sehr hohe Temperaturen (mittleres Maximum 34,7° C) und hohe Sonneneinstrahlung; anschliessend fallen die Temperaturen und die Lichteinstrahlung stark ab. Unter diesen Bedingungen bleibt die Infektion mit PLRV meist symptomlos und es gibt vom Pflanzenwuchs her keine Anzeichen dafür anzunehmen, dass der Ertrag beeintr?chtigt ist. Imersten Versuch (A) wurden die Ertr?ge von Best?nden verglichen, die die gleiche Pflanzgutgr?sse (Sorte Désirée) hatten, aber von drei Herkünften I, II und III stammten. Der Anteil der PLRV infizierten Knollen in diesen Herkünften betrug 1,3, 7,8 und 32,6% (Abb. 1A). Der durchschnittliche Ertrag pro Parzelle für Herkunft I, II und III lag bei 12,6 kg, 10,0 kg und 7,6 kg (Abb. 1C); die Differenzen zwischen den Herkünften waren signifikant (P<0,05). Der Unterschied zwischen Herkunft I und II gibt vielleicht die unterschiedlichen Auflaufraten wieder (Abb. 1B), aber die Differenz zwischen den Herkünften II und III scheint eine Folge der Virusinfektion zu sein, und ?hnliche Differenzen wurden beim Vergleich des Ertrages pro Pflanze gefunden (Abb. 1D). Diese Annahme wurde im Versuch B best?tigt, in dem der Ertrag PLRV-infizierter Pflanzen mit dem PLRV-freier Pflanzen verglichen wurde. Die Infektion mit PLRV war nicht mit einer verringerten Auflaufrate oder dem Ertrag an deformierten Knollen verbunden, aber infiziertes Pflanzgut der Sorte Blanka ergab nur 68,7% des Ertrages virusfreien Pflanzgutes, Up-to-Date 79,2% und Désirée 58%; die Verluste waren statistisch signifikant (Abb. 3). Diese Ergebnisse lassen annehmen, dass betr?chliche Ertragsverluste durch die Infektion mit PLRV in den im Herbst gepflanzten Kartoffeln eintreten k?nnen, obwohl die Symptome nicht wahrnehmbar sind. Im Hinblick auf den hohen PLRV-Befall in den Herbstbest?nden (Marco, 1981b), kann es von Vorteil sein die im Frühjahr gepflanzten Best?nde vor einer PLRV-Infektion zu schützen, da sie das Pflanzgut für den Herbst stellen.
Résumé Pendant les deux premiers mois de végétation des pommes de terre cultivées à l'automne en Israel (Ao?t-Janvier), les températures sont très élevées (moyenne maximale de 34,7°C) et la luminosité très forte. Puis les températures et l'intensité lumineuse diminuent rapidement. Sous de telles conditions, la contamination par le virus de l'enroulement est généralement existante mais sans l'apparition de sympt?mes; rien ne permet donc d'indiquer en végétation que le rendement est affecté. Dans une première expérience (A), le rendement est comparé pour trois cultures obtenues à partir de plants de même calibre (variété Désirée), mais de sources différentes (I, II et III). Suivant l'origine I, II et III les pourcentages de la contamination par le virus de l'enroulement est respectivement 1,3, 7,8 et 32,6% (fig. 1A). Le rendement moyen obtenu par parcelle est respectivement 12,6, 10 et 7,6 kg (fig. 1C), la différence entre les trois origines étant significative (P<0,05). L'écart de rendement entre les plants de source I et II s'explique sans doute par le taux de levée différent (fig. 1B); mais entre les plants de source II et III, la différence semble provenir de la contamination par le virus et ceci est également observé pour le rendement par pied (fig. 1D). Cette hypothèse est confirmée par l'expérience B ou le rendement obtenu à partir de plants contaminés est comparé à celui du témoin planté avec des tubercules indemnes de virus. L'incidence de la contamination n'est pas correlée au manque à la levée et au rendement des tubercules difformes. Les plants contaminés ont donné pour les variétés Blanka, Up-to-Date et Désirée respectivement 68,7%, 79,2% et 58% du rendement obtenu à partir de tubercules sains, la diminution de rendement étant significative (fig. 3). Les résultats montrent qu'il peut y avoir des相似文献
996.
Summary The effect of various storage parameters on the power usage and tuber weight loss for a fully refrigerated potato store were
investigated. A computer model validated by detailed monitoring of potato stores was used for the calculations. The store
parameters considered were: storage temperature, store relative humidity, local ambient conditions, store capacity or loading
factor, half cooling time and the infiltration rate or air tightness of the store. The investigation showed that the power
consumption was most affected by the storage temperature and the infiltration rate of the store, and that weight loss was
most affected by the half cooling time. 相似文献
997.
旨在研究小麦籽粒相关形态性状与粒重的关系,筛选籽粒形态性状优良品种,为小麦籽粒形态相关性状的遗传改良提供参考。以76个山西省主推小麦品种为试材,对小麦7个籽粒相关性状进行测量,运用主成分分析和聚类分析等方法对其进行分析和评价。供试材料的千粒重与籽粒面积、粒宽、籽粒周长、粒长存在极显著正相关,与籽粒长宽比负相关;依据综合评价值(D值)将参试小麦品种聚为3类,其中第Ⅰ-1类综合评价值最高,包括编号60、72的品种,平均D值达0.896,籽粒性状综合表现最好,尤其是千粒重、籽粒面积和籽粒周长。千粒重、籽粒面积和籽粒周长可作为小麦粒部性状考察的重要指标。 相似文献
998.
[目的]通过对知母种子的质量进行检测分析,比较不同来源知母种子的质量优劣.[方法]采用常规检验方法分别测定知母种子的净度、千粒重、发芽率、发芽势和生活力等指标.[结果]7种不同来源的知母种子质量上存在较大差异.[结论]陵川、襄汾、易县、亳州的知母种子质量较好,可作为知母生产引种繁殖的优选种质材料. 相似文献
999.
一种基于模糊的修复后土壤环境风险综合评价方法 总被引:3,自引:0,他引:3
Environmental risks pertaining to contaminated soils have been well studied, while little attention has been paid to the risks of the soils after remediation. In this study, a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators, namely, plant growth, groundwater safety and human health, of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover, great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general, the risks of both polluted and restored soils to the environment were in the order of groundwater safety 〉 plant growth 〉 human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers, which made it helpful in decision-making and management of restored soils. 相似文献
1000.
Shutao Dai Jinna Hou Maomao Qin Ziju Dai Xiaojie Jin Shilei Zhao Yanhua Dong Yongxia Wang Zhengqing Wu Zhensheng Lei 《中国油料作物学报(英文)》2021,6(1):28-34
Miniature inverted-repeat transposable elements(MITEs)are a group of DNA transposable element(TE)which preferentially distributed with gene associated regions.Tens of MITEs families have been revealed in Brassica napus genome,they scatter across the genome with tens of thousands copies and produce polymorphisms both intra-and inter-species.Our previous studies revealed a Tourist-like MITE,Monkey King,associated with vernalization requirement of B.napus,however there are still few studies reveal MITE association with agricultural traits in B.napus.In the present study,80 polymorphic markers were developed from 55 MITEs,and used to evaluate genetic diversity in a panel of B.napus accessions consisting of 101 natural and 25 synthetic genotypes.Five agricultural traits,oil content,glucosinolate content,erucic acid content,weight of thousand seeds(WTS)and plant height,were investigated across 3-years field experiments,in addition,two traits,hypocotyl length and root length,were evaluated at the 4-leaf stage in the laboratory.Correlations between the MITE-based markers and seven traits were analyzed,finally,10 polymorphic markers produced by 6 pairs of MITE specific primers were revealed relatively high correlation with 5 traits.Two polymorphic markers were anchored with two candidate genes,BnaA02g13530D and BnaA08g20010D,respectively,which may contribute to glucosinolate content and WTS.This research may contribute to genetic improvement through utilization of MITE-induced polymorphisms in Brassica species. 相似文献