红菜苔种子大小和种皮颜色对种子质量及苔产量的影响

该试验就红菜苔种子大小和种皮颜色对种子发芽势、发芽率、简化活力指数以及红菜苔植株的熟性、株平均苔数、单株苔重、单位面积苔产量的影响进行了研究。结果表明：（１）大粒种子的简化活力指数、株平均苔数苔重及单位面积的苔产量均显著或及显著高于小粒种子，而且，大粒种子植株现蕾比小粒种子早４－５天。但种子大小对发芽势、发芽率无影响。（２）深褐色种子的发芽势、发芽率、简化活力指数均显著或及显著高于深红色和灰褐色程     

不同营养类型烟株对种子产量和质量的影响

采用人工授粉方法,对5种不同营养类型的烟株进行杂交制种,以研究不同营养类型烟株对种子产量和质量的影响。结果表明:不同营养类型的烟株其种子产量和质量差异显著,处理间相比,以偏憨烟株种子的产量质量最高。因此,在烟草不育系杂交制种中,适当提高种株的营养水平,将制种烟株培育成偏憨烟株,可有效提高种子的产量和质量。这对烟草不育系杂交制种具有较大的指导意义。     

广金钱草种子适宜采收期研究

通过分析不同发育时期广金钱草种子产量、质量及生理生化物质的变化,确定广金钱草种子最佳采收期。结果表明,在盛花期10~25d长度和宽度增长迅速;绿色种皮比率逐渐降低,黄色种皮比率逐渐升高,依据果荚颜色、种皮颜色、种子硬度可将广金钱草种子成熟过程划分为:(1)绿荚期;(2)黄荚前期;(3)黄荚后期;(4)完熟期;(5)过熟期。种子发芽率在盛花期35d达到最大值79.67%,15~35d千粒重呈上升趋势,而单株产量在盛花期30d高达13.07g/株,是35d的2.07倍。可溶性糖和可溶性蛋白含量呈现上升趋势,SOD和POD活性表现为先上升后降低的趋势,SOD活性在盛花期30d达到最大值,POD活性在盛花期25d达到最高。因此,盛花期30d左右(黄荚后期)为广金钱草种子最佳采收期。     

蔬菜采种中的层性原理及应用

蔬菜作物种子的生理异质性,除受其遗传特性决定之外,还与该作物株型所特有的结构及种子(或果实)在种株上的着生部位有直接关系。即种子的质量和产量因种株的分枝习性及种子(或果实)在花序(或种株)上的着生部位不同而表现出差异,这就是“层     

蔬菜采种的层性原理及应用(上)

蔬菜作物种子的生理异质性,除受其遗传特性决定之外,还与该作物株型所特有的结构及种子(或果实)在种株上的着生部位有直接关系。换言之,即种子的质量和产量因种株的分枝习性及种子(或果实)在花序(或种株)上的着生部位不同而表现出差异,这就是层性原理。应用蔬菜采种中的层性原理,对提高蔬菜种子质量和产量将起到很大作用。只有重视们加强这方面的研究和推广,才能逐步实现种子标准化。     

大白菜杂交制种高产技术

大白菜在我国栽培的多种蔬菜中占着首屈一指的地位。保证生产上有数量充足、质量优良的种子,是关系到大白菜生产丰欠,市场均衡供应的大问题。一、适期播种,培育壮苗只有适期播种,才能使种株适时通过春化而抽薹开花,同时建立强大的同化体系,使种子产量高、质量好。播种过早,种苗过早地通过春化而抽薹开花,则种株不发达,降低种子的产量和质量。播     

基础种子纯度较低的原因及提高措施

<正>基础种子对农业生产用种安全起着非常重要的作用,优质的基础种子能提高品种的产量和质量,基础种子的纯度主要受育种家种子遗传性状、株行、株系种繁育程序以及基础种子管理措施的影响。随着种业市场的不断放开,影响基础种子质量的因素也越来越多。高质量的基础种子是生产高质量良种的源头。基础种子纯度越高,表现型就越趋于一致,生产出来的原种质量就越好,产量就越高。而基础种子纯度除决定于制种技术以外,主要受源头种子—育种家种子     

不同采果期多花黄精的果实成熟度及种子调制研究

[目的]研究多花黄精果实最佳采收期和种子调制方法.[方法]9月1日-11月1日每15d采收1次多花黄精果实,分析果实的颜色比例、百果重、百果体积、果实的纵径、横径和果实硬度;不同采收期的种子不同调制处理,分析种子千粒重、发霉率、生活力、发芽率、发芽势.[结果]绿果和半墨绿果的果实成熟度低,墨绿果的果实成熟度高;10月1日未见绿果和半墨绿果,黑软果出现;11月1日干枯果出现.9月1日、9月15日、10月1日采收的绿果分别发酵20,19,16d和墨绿果分别发酵19,16,4d种子质量最好;10月15日和11月1日采收的果实直接搓洗的种子质量较好.[结论]在种子生产中应该采摘墨绿果、黑软果和干枯果.10月1日至10月15日是贵州六枝地区的多花黄精果实最佳采收日期,此时绿果和墨绿果分别发酵16d和阴干处理的种子质量最好.     

药用作物黄精种子繁殖技术研究

研究了发酵漂洗和揉搓漂洗黄精果实对种子重要性状的影响,不同采收期黄精果实发酵漂洗获得种子的千粒重和发芽特性与种子分级, 不同贮藏方式对黄精种子萌发特性的影响.结果表明:黄精(P. sibiricum Red.)果实采收时间一般在11月中旬,多花黄精(P. cyrtonema Hua)和滇黄精(P. kingianum Coll.et Hemsl.)采收期在10月下旬,推荐采用发酵漂洗法处理黄精果实获得种子,推荐采用低温沙藏和冷冻沙藏保存种子.研究总结提出了黄精种子育苗技术规程.     

萝卜半成株采种法

萝卜采种的方式对于种子产量、质量和萝卜的产量等都有一定的影响。在生产中常见的采种方式主要有成株采种法、半成株采种法和小株采种法三种。成株采种法,其生产季节较长,母根往往偏大,不耐贮藏,易糠心腐烂。小株采种法生长期虽较短,但母根不能充分膨大,本品种的典型性表现较差,不能充分去杂去劣,所产种子质量也较差。半成株采种法     

Selection for pod retention and pod indehiscence in lentils

Summary The genetic variation for seed yield losses and the response to selection for reduction of such losses was studied by a six-week delay in the timing of harvest in various segregating populations from four lentil crosses. The bulk segregating populations had previously been subjected to different numbers of selection by means of a delayed harvest. The loss in seed yield from a delayed harvest in the two seasons 1981/82 and 1982/83 accounted for 551 and 105 kg/ha seed, representing 34 and 11% of the yield from a correctly timed harvest respectively. Pod drop accounted for 65% of this loss, whereas dehiscence gave 35% of the loss in both seasons. The parents of cross 4 differed significantly for pod dehiscence, with genotype 74TA 550 showing relative indehiscence. Selection by means of a delayed harvest of bulk populations decreased pod dehiscence, mean seed weight and bulk mean yield.     

How does the harvest index affect water‐use efficiency and nutrient‐utilization efficiency of sunflowers (Helianthus annuus L.)?

Besides oilseed rape and soybean, sunflower is one of the most important annual oilcrops. Apart from seed yield, which is the most important trait in many crops, oil yield is of utmost interest for sunflower breeders and farmers. Compared to the seed yield of sunflowers, their total biomass is often very high, and it is of great agronomic interest to increase the ratio of both parameters, which is defined as harvest index. With an increase in harvest index, improvements of resource‐use efficiencies can be expected. To generate an adequate seed yield, water and nutrients are key factors and their efficient use becomes increasingly important under conditions of aridity and higher production goals. A pot experiment was conducted in summer 2017 to determine differences in harvest index of various sunflower genotypes which could have an influence on the use efficiencies of water and nutrients (N, P, K). In total, 25 genotypes of different origin and with various morphological traits were investigated under optimal growth conditions. The harvest index varied from 29% to 47% and showed significant differences among some genotypes. The harvest index was less affected by the total biomass of the plants but more by the seed yield. The seed yield itself was mainly determined by the single seed weight rather than by the number of seeds. The experiment also confirmed significant positive correlations between harvest indices and all use efficiencies. Genotypes with high harvest indices were characterized by high oil concentrations in the seeds and particularly by high oil yields. In conclusion, cultivation of sunflower genotypes with high harvest indices most likely results in high water‐use efficiency and high nutrient‐utilization efficiencies as well as in high oil yields.     

蒙农红豆草不同成熟期种子的产量与品质分析

对不同生长年限及生长第4年早熟、常熟、晚熟、刈割后二茬收种的蒙农红豆草种子进行产量构成因子、种子产量及品质测定分析.结果表明:在呼和浩特市地区6月30日前成熟(早熟)的蒙农红豆草种子产量与品质最佳;在花蕾期刈割收草,二茬收种也是一种较好的利用方式,虽然种子产量稍低,但种子品质与早熟种子相当.关健词蒙农红豆草种子产量种子品质采种期     

逆境下广布野豌豆的适宜收获时间

及时收获对于获得最大的种子活力和种子产量是很重要的,许多牧草都具有种子脱落及其他种子生产的问题。裂荚是广布野豌豆种子生产中的一个重要问题。本文的研究目的是通过分析种子和荚果的生理学特征、种子的抗逆能力来进一步确定广布野豌豆(Vicia cracca)的收获时间。在广布野豌豆荚果发育过程中,每隔3 d收获1次荚果,到荚果开始出现开裂为止(盛花后第42 d)。结果显示,盛花后36~42 d,荚果干重、千粒重达到最大及荚果含水量达到最小,在此期间NaCl和Na₂CO₃胁迫下的种子发芽率、发芽速率及胚根长均达到最大值。因此,广布野豌豆在裂荚前6 d收获不影响种子产量和品质。     

Associations of some characters with seed yield in chickpea collections

Summary Three thousand two hundred and sixty-seven kabuli chickpea (Cicer arietinum L.) germplasm accessions were grown during the spring season of 1980 at Tel Hadya, the main research station of ICARDA, Syria to determine the components of seed yield. Observations were recorded on seed yield and 14 other characters. Correlation and path coefficient analyses were done to find out associations among characters and to assess the direct and indirect contribution of each character to seed yield.Large variation was observed for all the characters studied except days to flowering, days to maturity and protein content. Correlation and path coefficient analyses showed that biological yield and harvest index were the major direct contributors to seed yield. The 100-seed weight, plant height, days to flowering and maturity, canopy width, and protein content contributed to seed yield mainly through indirect effect via biological yield and harvest index. The 100-seed weight and seed yield were major contributors to biological yield. Major contributor to protein content was days to maturity. Results indicated that selection for high biological yield and harvest index would lead to high seed yield; and selection for large seed size would lead to high biological yield. Therefore, these characters should receive the highest priority in selecting high yielding plants in chickpea breeding.     

Seed yield related to crop development and to yield components in nine cultivars of perennial ryegrass (Lolium perenne L.)

Summary We had previously found differences for seed yield among nine perennial ryegrass cultivars which were not associated with variation for seed weight. To detect the physiological basis of these genetic differences for seed yield, growth analyses were carried out. We related crop development and components of seed yield to seed yield during three years on clay and sandy soil. No significant differences occurred among cultivars for accumulation and partitioning of dry matter or the pattern of tiller production. Seed yield of the cultivars was not associated with ear number or total dry matter yield of the seed crop. Seed yield was more correlated with the number of seeds per unit area than with seed weight. The number of seeds as calculated after harvest from seed yield and seed weight was much lower than the number of seeds as estimated prior to harvest from seed yield components. The number of spikelets differed significantly among the cultivars, but the ranking was different from that for seed yield. The physiological basis of the genetic differences for seed yield is not clear. Implications for breeding perennial ryegrass are discussed.     

Implications of selecting improved strains of soybeans for dry-matter accumulation and grain yield

Summary Three maturity groups of soybeans (Glycine max L.) were used to investigate the relationship between dry-matter accumulation (DMA) and grain yield (GY), and the prospects for selection of high seed yielding strains among the existing soybean cultivars in a tropical environment. The positive and significant association between DMA and GY (r=0.888^***) indicated that selection for high DMA could give gains in GY. However, the higher harvest index (HI=37.5%) for the low seed yielding early maturing genotypes than the more vegetatively endowed and higher seed producing late maturity group, is an indication that excessive DMA could be disadvantageous. Total seed yield per land area for the three maturity groups of soybeans showed that the genotypes with high harvest index and low seed yield could be as good as those ones with high seed and dry-matter yields with low harvest index. The high coefficient of variation which ranged between 18.1 and 59.8% and the heritability estimations which also ranged from 34.4 to 82.2% are indicative of the presence of substantial genetic diversity and there are good prospects for the improvement of the crop through selection.     

Some Agronomic Strategies for Organic Quinoa (Chenopodium quinoa Willd.)

Quinoa is a potential new seed crop for protein feed and human consumption in Europe, with tolerance to a range of abiotic stresses. For this purpose the study was planned to analyse the effect of important agronomic strategies like nitrogen level, N application strategy, row spacing and harvest time on yield and quality of quinoa. The experiments took place in the field of the experimental station of the Faculty of Science, University of Copenhagen. Three levels of organic nitrogen from slurry was used (60, 120 and 180 kg N ha^?1), supplied either all at once at sowing, or split between sowing and beginning of the reproductive phase. The effect of row spacing and harvest time was studied by harvesting seeds at seed maturity, which occurred 2–3 weeks prior to the mechanical harvest by threshing, and a couple of months after. Yield increased significantly (P ≤ 0.05) with an application up to 180 kg N ha^?1, reaching 2200 kg ha^?1. Increasing N also caused a significantly increased seed weight (up to 3.3 mg) and protein content (up to 17 %). N level did not affect number and amount of weeds. Split application with part of the N applied at bud formation did not have a significant effect on yield. Delayed harvest had a negative influence on seed weight, whereas protein content was stable after harvesting even a month after seed maturity. A late harvest significantly reduced seed germination, being reduced by 50 % after a 2‐month delay. A conclusion from this study is that both yield and protein content of seed can be manipulated by N level and application strategy. Harvest time is important for securing a high seed quality measured as seed germination, seed weight and protein content. A fast germination of quinoa is an important characteristic demonstrating that the crop has good possibilities for being well‐established in the field when free from weeds at the time of sowing. The choice of row spacing is important and depends on weed control method. Weed control strategy should be developed based on modern precision tools.     

Estimates of relative contribution of biomass, harvest index and yield components to soybean yield improvements in China

A method was developed to estimate the relative contribution of increased biomass, harvest index and yield components to seed yield gain of soybean. Data from four field experiments conducted in three soybean production regions in China were used to measure the role of different traits (such as harvest index) in seed yield improvement by applying this method. The results indicated that harvest index was a larger contributor to the progress of soybean yield improvements than biomass in China. However, the estimates of improvements of yield components suggested that there could be several strategies for obtaining high yield. High yielding would be achieved by improving all of the three yield components (pods per plant, seeds per pod and seed weight) simultaneously, or significantly improving one or two of the three components.     

Monocarpk Senescence in Relation to Yield of Sesamum indicum During Source-Sink Alteration

Defoliation hastens senescence of the capsule wall, increased seed weight/capsule and harvest index, promotes seed filling and decreased the post-flowering contribution and yield/plant. Defruiting delayed senescence of the subtending leaf. Treatment of kinetin on the capsule wall increased its chlorophyll, sugar and dry weight and also increased yield by increasing harvest index, seed weight/capsule compared to seed treatment as well as control, although post-flowering contribution reduced significantly. When treated on the capsule wall ABA defers senescence of both leaf and capsule wall and also increased the yield parameters but seed treatment although defers senescence of both the source organs, decreased the yield parameters. Treatment of urea defers senescence of the source organs and also increased yield and capsule number though harvest index was reduced.
It is concluded that contribution from the capsule wall and deferment of senescence of this organ at the post capsule development period determines yield and in normal condition contribution of source is limited by the sink size.