栽培方式对多花黑麦草种子生产性状及产量的影响

为探讨冬闲田栽培方式对多花黑麦草种子生产的影响,田间采用条播和撒播2种栽培方式繁育多花黑麦草种子.结果表明,2种栽培方式繁育种子,多花黑麦草均能完成生育期,种子成熟度高,不影响接茬水稻种植,条播多花黑麦草种子生育期比撒播种子生育期短6d,种子产量条播多花黑麦草比撒播黑麦草提高23.19％,发芽率条播多花黑麦草比撒播多花草提高2.46％.在南方山区利用冬闲田繁育多花黑麦草种子时采用条播栽培方式较好.     

多花黑麦草的主要栽培技术

多花黑麦草适应性强,对环境要求不严,耐酸耐瘠,抗病抗虫,易栽易管,产量高,营养丰富,适口性强,消化利用率高。各地实践证明,以多花黑麦草饲喂牛、猪、鱼等,经济效益显著。现将多花黑麦草的主要栽培技术介绍如下:1.精细整地多花黑麦草种子小而轻,顶土能力弱,千粒重仅1.3~2.0克。为保证其顺利出苗,整地质量要求较     

贵州省贵草1号多花黑麦草种子生产技术规程

为了规范贵州省贵草1号多花黑麦草的生产,针对贵州省贵草1号多花黑麦草种子生产基地中的实际情况,依据国家、行业标准,对贵草1号多花黑麦草种子生产的环境条件、播种、田间管理和检验、收种、清选、贮藏等提出了具体要求和规定.该生产技术规程对贵州乃至西南诸省多花黑麦草种子的生产具有重要的现实指导意义.     

多花黑麦草幼穗分化进程对种子生产性状的影响

多花黑麦草幼穗分化进程对穗部性状和种子产量有显著影响。幼穗分化的天数与每穗种子粒数是极显著正相关。播种愈早，幼穗分化天数愈多，种子产量愈高。南京地区留种的多花黑麦草的最佳播期8月20日19月10日。二棱期是多花黑麦草通过春化阶段的形态标志，也是幼穗能否分化完全的转折点。单棱至护颖分化期是影响种子粒数最关键的时期。     

甘蓝型油菜隐性核不育系98-116 AB原种的保优繁殖技术

根据甘蓝型油菜隐性核不育系98-116AB生长发育特点和品质特性进行保优繁殖技术研究,在严格的隔离条件下进行原原种和原种亲本的保优繁殖技术研究,制订了既可连年保证所配杂交种的产量优势和增产潜力,又可防止不育系亲本优良种性和品质因繁殖代数增加造成混杂退化的隐性胞核雄性不育两系的原种繁殖技术规程。     

甘蓝型油菜隐性胞核雄性不育杂交种恢复系的原种繁殖技术规程

通过研究与实践验证,总结并制订了既可连年保持所配杂交种的产量优势和增产替力,又可防止其优良种性和品质因繁殖代数增加造成混杂退化的隐性胞核雄性不育杂交种恢复系的原种繁殖技术规程:即一级原原种干燥低温保存,以后5—6年内分年取种隔离繁殖二级原原种,翌年又以之作供繁种进行原种繁殖,生产原种下年再用于大田制种。     

滇东北退耕还草中牧草种子生产及其产量分析

2001至2003年在滇东北金沙江流域干热河谷高海拔山区,即云南昭通地区彝良县海拔2 000 m的半山区进行了植被恢复和退耕还草试验示范.试验选择了15个草种,共19个品种进行单播.对种子产量和牧草产量进行了测定和分析.结果表明:在彝良高海拔山区适宜种植的一年生牧草有高丹草和箭舌豌豆,其鲜草产量均较高.在短年生和多年生牧草中,多花黑麦草(旺饲)鲜草产草量最高,第二年鲜草产量达170 895.84 kg/hm2;多年生黑麦草和红三叶鲜草产量相近,在155 000 kg/hm2左右;鲜草产量由高到低依次为多花黑麦草(旺饲)>多年生黑麦草>红三叶(多丽)>鸭茅(牧友)>高羊茅>紫花苜蓿(WL-612)>紫花苜蓿(普拉多)>白三叶>猫尾草.这些牧草均可以用于金沙江干热河谷海拔2 000 m的山区植被恢复和草地建设.本研究中筛选出适宜金沙江干热河谷海拔2 000 m的山区进行牧草种子生产的草种,分别为:多花黑麦草(旺饲)(1 430.00 kg/hm2)、紫羊茅(760.00 kg/hm2)和苇状羊茅(733.00 kg/hm2).多年生黑麦草、红三叶、鸭茅、白三叶等牧草种子产量可达400～500 kg/hm2.     

花魔芋种子有性繁殖提纯复壮技术

正1.技术背景花魔芋有性繁殖是解决生产上急需大量优质、纯度高、健康种子资源的有效措施。种子有性繁殖提纯复壮是增强种性,为大面积生产提供优质魔芋良种,提高魔芋种植产量、质量、产量、经济效益的关键的最有效的途径技术。同时也是开展魔芋种内和种间杂交育种的基础。本文重点论述了魔芋种子有性繁殖提纯复壮技术措施。花魔芋种子有性繁殖纯复壮技术关键抓好8个方     

紫茎泽兰对两种牧草发芽的化感克异作用

研究了紫茎泽兰地上部分、根系及根际土壤不同浓度提取液对白三叶和多花黑麦草发芽的影响。研究结果表明：紫茎泽兰对白三叶和黑麦草种子萌芽存在化感克异现象，并且随浓度的增加，影响越大；相同条件下，对白三叶的影响强于多花黑麦草；低浓度对白三叶败育的影响较大，但对多花黑麦草几乎没有影响；紫茎泽兰根际土壤对两种牧草种子萌芽无明显的化感克异作用。     

不同除草剂防治棉田田旋花效果分析

<正>田旋花又称箭叶旋花,属旋花科多年生慢性草本植物,是一种顽固性多年生恶性杂草,其繁殖和再生能力极强,可通过根芽或种子快速繁殖。田旋花在当地农田杂草中属于优势种群,尤其在棉田中与棉花争光、争水、争肥,致使棉花生长衰弱,抗虫抗病性差,严重影响了棉花的产量和品质,同时还是叶螨早     

串叶松香草种子产量构成因子分析

采用方差分析、相关分析、通径分析和逐步回归分析对串叶松香草种子产量构成因子进行了研究,结果表明:在串叶松香草株高、每株生殖枝数、每株花序数、每花序种子数、千粒重和单株种子产量这6个产量因子中,除株高和千粒重在不同生长年限之间不存在显著差异外,其它因子均存在显著差异;每株花序数和每花序种子数与单株种子产量间存在极显著相关,是串叶松香草种子产量的主要影响因子;串叶松香草单株种子产量的回归模型为:Y=-87.50047+0.14578X3+4.19497X4(F=23.51,Pr0.0001)。     

刈割时间对苜蓿生殖生长及种子性状的影响

试验以‘新牧4号’紫花苜蓿为材料,研究不同刈割时间对苜蓿生殖生长及种子特性的影响,以期为提高苜蓿种子产量提供基础数据。试验数据表明,刈割对苜蓿生殖格局、种子产量和种子特性等影响较大。其中,返青后第44（5月8日）、51天（5月15日）刈割,与对照相比,种子千粒重分别增加24.44%、30%,种子产量分别提高26.85%、45.86%,种子发芽率分别降低了2.12%、10.63%。刈割能够延迟苜蓿花期,通过改变苜蓿花期的外部环境和花的传粉效率来影响其结实特性。在苜蓿孕蕾至初花期间,适时刈割1次,能够提高花的传粉受精效率,降低生殖败育率,增加种子产量。     

Intercropping soybean and palisade grass for enhanced land use efficiency and revenue in a no till system

Integrated no-till crop and livestock production systems may help rejuvenate degraded pastures, increase land use efficiency (LUE), and increase enterprise revenue. Our objectives were to evaluate: (1) planting date effects on seed yield and nutrient concentration of an early-maturing, no-till system (NTS) soybean (Glycine max) when intercropped with palisade grass (Brachiaria brizantha); (2) dry matter production and protein concentration of the grass pasture after soybean harvest; and (3) overall revenue and LUE for the intercrop system. Experiments were performed during two growing seasons in Botucatu, Brazil using a randomized complete block experimental design. When palisade grass and soybean were sown simultaneously, soybean yield averaged 3.28 Mg ha⁻¹. Similar seed yields were observed when palisade grass was planted either 30 d after soybean emergence (DAE) (3.29 Mg ha⁻¹) or at the soybean reproductive stage R6 (full seed) (3.50 Mg ha⁻¹). Monocrop soybean yield averaged 3.50 Mg ha⁻¹. First cut dry matter forage production was greater when palisade grass was sown at the same time as soybean or 30 DAE of soybean. This indicates that interseeding palisade grass with soybean does not significantly affect soybean nutrition or yield. Intercropping did increase LUE and resulted in 1.6 times more revenue than soybean alone. However, sowing palisade grass at the soybean reproductive stage R6 (full seed) significantly reduced the forage yield compared to early planting.     

水稻原种不同代别的纯度与产量效应及其相关性研究

选用本区单季晚粳稻品种“早单八”,对其原种不同代别的种子进行了纯度与产量以及相关性状的比较研究。结果看出:随原种种植代别的增加,田间纯度逐代下降,两者呈高度负相关(r=-0.868~(**)),而各代别的纯度与产量则存在极显著正相关(r=0.954~(**))。低代别种子之所以具有较高的生产力,拟主要通过提高结实率表实现的。进一步分析还看出:原种不同代别的杂株本与产量存在极显著的回归关系,其回归方程为Y=564.32—9.38X。综上表明:以田间杂株率高低来估计不同代别纯度种子的实际产量,将有一定的实践意义。按该方程推算,原种代别利用的临界纯度拟应为98%,原种连续种植的实际年效应最多为4年。     

Uniformity, Performance and Seed Quality of Soybean (Glycine max (L.) Merrill) Seed Crops Grown from Sub-samples of One Seed Lot Obtained after Selection for Physical Seed Attributes

In a glasshouse experiment it was examined whether narrow grading and selection from a commercial soybean seed lot cultivar 'IAS-5', could improve the uniformity of the seed crop grown from it and thereby enhance yield, quality and uniformity of seeds produced. The classes created were: Control (original seed lot); Size-graded seeds (projected area measured by image analysis 37–46 mm²); Non-cracked seeds; Yellow seeds; Size-graded sound seeds (size-graded, non-cracked, yellow, non-wrinkled, non-etched). Compared to the control, percentage of emergence, survival and number of yielding plants were enhanced in crops from non-cracked, yellow or size-graded sound seeds. Differences in plant numbers did not result in differences in crop yield. The different seed lots also did not differ in crop uniformity: time interval between stages of plant development, plant height 20 days after sowing, yield components, physical or physiological quality attributes of seeds produced, and respective coefficients of variation were similar. Fewer plants survived in crops showing a larger variation in plant height 20 days after sowing, thus reducing differences in initial plant-to-plant variation. Creating more uniform crops by additional grading or selection of commercial seed lots may therefore not be promising.     

Influence of Seed Quality on Field Establishment and Forage Yield of White Clover (Trifolium repens L.)

Two seed lots of white clover ( Trifolium repens L.) cultivar 'Makibashiro' classified as high and poor quality seed lots, based on the speed of germination (T50), were used to examine the influence of seed quality on field establishment and forage yield. Field emergence rate was estimated approximately three weeks after sowing and found that plots sown with high quality seeds (Lot 1) had 452 seedlings m^-2 compared with 392 seedlings in the plots sown with low quality seed lot (Lot 2), but the difference was not significant. However, plant density in autumn (November, 1993), 3 months after sowing, was significantly (P < 0.05) higher in the plots of the Lot 1 seed than that from the Lot 2 seed. The percentage of clover plants surviving over the winter from Lot 1 plots was 55% compared with 39% from the Lot 2 plots, but the difference was not significant. Total forage yield in Lot 1 plots harvested in July and monthly intervals to October, was significantly increased by 44% (P < 0.05) over that of Lot 2 plots, but this greater forage yield in high seed quality seed lot plots was produced early in the season. The results strongly imply that the primary advantage to be gained from high quality seed is an improved field establishment, which led to increased yield of clover. In Lot 1 plots, the percentage of weed dry matter in all the four harvests remained below 1% of die seasonal dry matter production, whereas in Lot 2 plots die percentage of weed dry matter ranged from 3.3–16.9%.     

Reproductive Abscission and Yield of Irrigated and Drought Stressed Cowpea

Two experiments were conducted under field conditions to evaluate reproductive abscission, seed yield and yield components of three cowpea [Vigna unguiculata (L.) Walp.] genotypes. In the first experiment, level of abscission and yield of two cultivars, California Blackeye Pea No. 5 (CA-5) and Speckle Purple Hull (SPH), and one experimental line (AZ-54) were studied. In the second experiment, effect of drought stress on abscission at three nodal positions, seed yield, and yield components of CA-5 were studied. Abscission in both experiments was determined by counting scars left by dropprd reproductive structures including floral buds, open flowers, and immature pods. Abscission of CA-5 and AZ-54 in the first experiment ranged between 68 and 76 % while that of SPH ranged between 86 and 89 %. CA-5 and AZ-54 retained two to three pods per peduncle, and SPH retained only one mature pod per peduncle. Average seed yields of SPH and AZ-54, respectively, were 45 and 50 % of CA-5. Drought stress in the second experiment did not affect production of floral buds Peduncle^?1 (average of 10) but significantly increased percent reproductive abscission and decreased pod retention of CA-5. Abscission in the bottom two-third nodes increased from 82 % in well-irrigated plants to 93 % in non-irrigated plants. This increase in abscission corresponded to nearly 60 % reduction in pod retention. The number of pods per peduncle in the bottom two-third nodes decreased from 1.9 in well-irrigated plants to only. 77 in non-irrigated plants. The increase in abscission and decrease in pod retention with increasing intensity of drought was greatest in the bottom one-third nodes. Drought stress did not affect abscission and pod retention in the top one-third nodes. Stress also decreased peduncles plant^?1, seeds pod^?1, and dry matter and seed yield plant^?1 but did not affect seed weight and harvest index. The decrease in seed yield was largely due to reductions in pods plant^?1 and seeds pod^?1. The reduction in the number of pods and, therefore, seed yield due to stress was because of reductions in the number of peduncles plant^?1 and increases in reproductive abscission. It is concluded external conditions that increase abscission beyond that of normal occurrence affect seed yield adversely.     

Relationships between Seed Yield and Chemical Composition of Field Peas Grown under Semi-arid Mediterranean Conditions

Relationships between seed protein, lipid, starch and sugar concentrations and seed yield of 14 pea (Pisum sativum L.) cultivars were examined under rain-fed conditions in northern Jordan. Significant differences amongst cultivars for each character were noted. The cultivar-by-environment interaction was significant for each character except lipid and starch concentrations. A negative correlation was noted between seed yield and seed protein and fructose concentrations. Positive non-significant correlations between seed yield and seed lipid and starch concentrations were noted. The cultivars DMR-8, P 350-1 and 88P022-6 had similar seed yields, but varied seed chemical components. Seeds of the Praire No. 11 cultivar had the highest protein concentration amongst cultivars, although it produced the lowest seed yield. These results indicate that factors other than seed yield are important for determining the chemical composition of seeds, and that one-sided selection for high seed yield tends to reduce the nutritional quality of the pea seed.     

Components of Seed and Straw Yield in Common Vetch (Vicia sativa L.)

178 common vetch (Vicia sativa L.) strains were tested for 2 years under dryland conditions in Bursa, Turkey. Broad-sense heritability of the traits was calculated for each trait. Phenotypic and genotypic correlation coefficients between seed and straw yield, with several morphological and reproductive traits, were obtained. Broad-sense heritability estimates were high for 1000-seed weight and number of seeds per pod. Heritability values for both seed and straw yield were small and insignificant. Harvest index, 1000-seed weight and spring vigour showed significant positive correlations with seed yield, but days to flower correlated negatively with seed yield. Spring vigour, plant height and number of leaflets per leaf correlated positively, while harvest index, seeds per pod and seeds per plant correlated negatively with straw yield. Correlations between seed and straw yield were both positive and significant.     

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.