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31.
天畅5号是农家品种杨家豇豆与之豇28—2杂交,并通过系统选育而成的极早熟豇豆新品种。该品种表现早熟,叶片小。以主蔓结荚为主,有侧蔓1-2个,始花节位2-3节。成荚率高。每花穗结荚2~4条,前期产量较高。嫩荚白绿色,荚条长而直,荚长65cm,单荚质量22g。荚条肉质脆嫩,品质优,商品性极佳。春播从播种到商品荚采摘期为52天。露地种植的产量1800-2500kg/667m2,适于长江流域栽培。  相似文献   
32.
Summary The potential of isozymes for distinguishing asparagus varieties was carried out by a survey on 21 varieties using 10 enzyme systems: GOT, SkDH, DIA, PGM, MDH, IDH, PGD, ACP, PGI, MR and ADH. Only 3 enzymes, SkDH, GOT and PGM, showed useful polymorphisms. The varieties were found heterogeneous according to their genetic structure: open pollinated varieties were more heterogeneous than clonal hybrids; the F1 hybrid and the vitroclones were homogeneous. As expected from the narrow genetic basis of the varieties, only a few alleles per isozyme locus were present. Moreover, for each enzyme, one allele or type was predominant so that the discriminating power of the method was low. However some of the varieties could be identified and different applications of the results are presented.Abbreviations D.U.S.- Distinction-Uniformity-Stability - ACO- aconitase - ACP- acid phosphatase - ADH- alcohol dehydrogenase - CAT- catalase - DIA- diaphorase - END- endopeptidase - GOT- glutamate oxaloacetate transaminase - IDH- isocitrate dehydrogenase - MDH- malate dehydrogenase - MR- menadione reductase - PGI- phosphoglucoisomerase - PGM- phosphoglucomutase - PGD- phosphoglucose dehydrogenase - POX- peroxidase - SkDH- shikimate dehydrogenase  相似文献   
33.
采用天冬单作、玉米单作和天冬-玉米套作3种种植模式,考查了整个生产过程中其主要生产资料和劳动力的投入以及产值等关键指标.对不同种植模式的经济效益对比分析结果表明,天冬-玉米套作比天冬单作增收21.8%,比玉米单作增收564.9%.天冬单作虽比玉米单作增收446.0%,但天冬种植三年后才能收获药材,没有短期收益.因此,3种模式中天冬-玉米套作的效果最佳.这一研究结果为种植业提供了一条"粮-药间套"的有效增益模式.  相似文献   
34.
Asparagus is especially suitable for polyploidy breeding. The aim is to develop clone-based hybrid varieties, in particular male 4 × varieties. For this purpose, genetically divergent diploid idiotypes * * Idiotye (according to Reiger et al. 1976) is the sum of total hereditary determinants of an organism, consisting of its genotype (all determinants localized in the chromosomes) and its plasmotype (all determinants localized extra-chromosomally).
) are subjected to mitotic or meiotic polyploidization. In developing hybrid partners, special attention is paid to resistance in addition to yield and quality characters. Early diagnoses are applied in selection so as to shorten breeding times. Somaclonal variations may occur relatively often on in vitro propagation; these need to be eliminated. Triplex and quadruplex type males are suitable for paternal hybrid partners. Strong inbreeding depressions need to be avoided in their production.  相似文献   
35.
芦笋采收期间,发茎数和产量在4月21日左右和5月中旬有二个高峰,采收后期的产量和发茎数下降,次品率较高;空心笋主要在4月份发生;白芦笋的空心率高于绿芦笋。产量、茎数及地温之间呈极显著正相关,空心率与地温显著负相关。维生素 C 含量以开始采收时最低,绿芦笋的维生素 C 含量在4月26日最高,白芦笋的维生素 C 含量采收后期较高,在整个采收期间绿芦笋的维生素 C 含量始终高于白芦笋。粗纤维含量以4月份最低,以后逐渐增加。  相似文献   
36.
本文描述了芦笋两个品种花的形态,用体视显微镜观察了芦笋品种玛丽华盛顿的雄花、雌花、两性花和芦笋品种UC72雄花、雌花、变异雌花。我们比较了这些花的主要特征,发现一些显著的差异,可能两性花是雄花与雌花的中间类型,单子叶植物与双子叶植物的区别不是绝对的。  相似文献   
37.
为建立芦笋单倍体育种技术体系以解决国内芦笋新品种资源贫乏问题,该文以白芦笋花药为外植体进行了愈伤组织的诱导及绿芽分化研究。试验结果表明,芦笋花药经过4d的冷藏(4℃)处理后,接种于含有NAA2.0mg/L、6-BA 1.0mg/L及6%蔗糖的1/2MS培养基上,可产生愈伤组织;每年的4月份接种花药的愈伤组织诱导率最高,8月份次之,11月份最低。品种间、同一品种不同单株间花药的愈伤组织诱导率不同,以‘UC155’品种(18.9%)最高,显著高于其他三个品种‘UC142’(11.6%)、‘Gijnlim’(10.3%)、‘Thielim’(5.8%),所有试验株系中以‘UC155’-8的愈伤组织诱导率最高,达83.5%;每日补充光照强度为1000lx的光照,比全暗培养更有利于芦笋花药愈伤组织的形成;花药接种前进行离心处理(4000r/min)30min,不能提高愈伤组织诱导率;愈伤组织转瓶培养于NAA0.5mg/L、6-BA1.0mg/L及3%蔗糖的MS培养基上,能分化出无根绿芽;不同品种间绿芽分化率有差别,以‘Gijnlim’品种最高(67.2%),‘UC142’品种最低(14.1%);未分化绿芽的愈伤组织再转入于不含植物生长调节剂的MS培养基上培养,部分愈伤组织能分化出绿芽。  相似文献   
38.
This study aimed to answer the following questions (a) which of the soil variables (chemical, biological, enzyme activities and potential metabolic profile based on the Biolog method) could be used as indicators reflecting differences in soil quality between organically and conventionally managed asparagus fields, (b) how the duration of organic management affects these soil variables and (c) in what extent the soil quality in organic fields is comparable to that in hedgerows. The study included four organically cultivated fields which differed in the time they enter organic treatment: 6 years (O6), 5 years (O5), 3 years (O3) and 2 years (O2), the closest to them hedgerow (Ho), a conventionally managed field (CF) and its adjacent hedgerow (Hc). Among the chemical and biological variables, those contributing for most to the discrimination of the organic and conventional fields were mainly microbial biomass C (MBC) and N (MBN) and secondly variables related to N-cycle (NO3, N organic, rate of N mineralization). MBC and MBN were higher in organic and conventional areas, respectively, reflecting differences in the structure of their microbial communities. The chemical and biological variables did not differ among O3, O5 and O6 fields, while low values of organic N, rate of N mineralization and extractable P was recorded in O2 area. The enzyme activities of amidohydrolases (l-asparaginase,l-glutaminase, urease) and phosphatases (alkaline and acid phosphatase) were by far higher in organic areas than in the conventional one. The activities of amidohydrolases and alkaline phosphatase changed in a similar way, exhibiting higher values in O3 and O5 areas while between the oldest (O6) and the newest (O2) area no differences were recorded. While the suppress of enzyme activities in O2 was related to low inputs due to transition, the negative feedback between supply of N and P and activities in O6 was a possible explanation. The activity of acid phosphatase increased from the newest to oldest organic areas. The potential functional diversity and substrate evenness did not differ among sampling areas. Differences between areas were recorded only in relation to the carbohydrates' consumption. The soil quality of hedgerows seems to be completely different than that of the arable land in terms of all studied variables. Also, significant differences were recorded between the two hedgerows, a fact that could be related to the different management practices applied in the neighboring fields.  相似文献   
39.
对芦笋在冷藏及焯烫、冷冻、制罐、清炒等不同加工条件下的感官品质变化与细胞结构变化进行了研究。通过实验可知在各种加工及冷藏条件下,芦笋的感官质量与组织结构中的表皮、薄壁组织、导管等均会受到影响,而且与加热时间的长短、温度的高低及是否受冻有密切的关系。  相似文献   
40.
[目的]确定合理的芦笋(AsparagusoffwinalisL.)灌水控制指标。[方法]采用盆栽试验,设置3个灌水下限(80%~85%fc、65%~70%fc、45%~50%fc),研究不同灌水下限对沙培芦笋生长生理指标的影响。[结果]灌水下限对芦笋生长状况和生理指标均有显著影响。45%~50%fc灌水下限条件下植株生长发育良好,根数多,主根长;一定范围内,MDA含量和SOD、POD、CAT活性随着灌水下限的提高明显增加,说明较高的灌水下限可能一定程度上对芦笋形成了胁迫,芦笋可通过提高体内的抗氧化酶活性来减轻由此带来的伤害。因此,选择土壤相对含水率45%~50%fc作为沙培芦笋的灌水下限指标。[结论]不同灌水下限是影响芦笋生长生理指标的主要因素。该研究可为沙培芦笋生产提供科肇依据.  相似文献   
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