甜菜种子发芽率变动规律及影响因子初探

对甜菜种子发芽率变动规律及影响因子分析表明,二倍体甜菜种子发芽率高于多倍体甜菜,且样本间变异系数大;中粒型种球即可满足育种及用种单位对发芽率的要求;正常情况下黄或黄褐色种球发芽率高于黑褐色种球;于种子休眠期可测得准确发芽率;“挖心”去顶端优势法种子发芽率高于“打顶”法;此外合理的栽培措施及肥水运筹均可提高种子发芽率。     

棉花水育苗不同育苗专用肥试验简报

以农杂66F1为试验材料，在湖南省常德的鼎城和澧县两个试验点，对4种不同育苗肥（棉花水育苗肥Ⅰ号，水育苗肥Ⅱ号，营养钵苗床肥和对照）作用下棉花的发芽率、成苗率、移栽后的生长发育动态以及棉花产量进行了研究。结果表明：棉花水育苗肥Ⅰ号和Ⅱ号能够显著的提高发芽率、成苗率；缓苗期缩短5～7d；生育期提早4～5d；子棉产量比对照增加450～585kg／hm^2，比营养钵育苗肥处理增产285～525kg／hm^2；皮棉产量比对照增加150～210kg／hm^2，增产幅度为9．5％～14．4％，比营养钵育苗肥处理增加150～185kg／hm^2，增产幅度为9．9％～13．6％。     

母根浅窖贮藏繁殖甜菜单粒种

黑龙江省国营农场总局所属农场,种植甜菜面积较大,机械化程度高,适宜推广遗传单粒型品种。目前,甜菜采种普遍采用南方露地越冬法,但遗传单粒种在南方露地越冬采种的结果,种子单产只有60～80kg,种球千粒重在8g左右,种子发芽势弱,发芽率仅在40％左右,种子加工成品率在7％左右。为了改善甜菜采种条件,黑龙江省国营农场总局种子公司经多方面考证,将遗传单粒型品种采种区改在山东省济南地区黄河以北的齐河县,采用母根浅窖贮藏法繁殖遗传单粒型品种,获得了平均亩产150kg,为露     

棉花包衣种的优势及应注意的问题

棉花色衣种是指毛棉籽经泡沫酸脱绒，精选、药肥包衣、装袋系列加工处理后的成品种子。具有成熟度好、发芽率高、棉苗素质好、病害轻等优点。是实现棉种产业化的重要基础，我市自1994年试验、示范和大面积推广应用，种植面积达17000hm2，占棉田面积的95％以上。1包衣种具有六大优势1．1增产效果显著包衣种皮棉产量1519．skg·hm-2比ck（毛籽，下同）1359kg·hm-2增加115．5kg，增产11，8％。1．2播种品质好包衣种健子率94．2％，比ck75．5％高18．7个百分点；发芽率包衣种83．3％，比ck73．5％高9．8个百分点；发芽势包衣种70％，比ck55％高…     

黑玉米新品种延黑1号的选育报告

延黑1号黑玉米系延安市农业科学研究所于1998年育成的黑玉米综合杂交种,其子粒皮色深黑发亮,粉质型,穗轴紫黑色,幼苗茎紫红色,叶片中脉紫红色,株高250 cm以上,穗长23 cm,千粒重345 g,产量6 800kg/hm²,生育期120～125 d,抗大、小斑病和青枯病,感黑粉病.子粒营养丰富,含淀粉68.55%,赖氨酸0.37%,微量元素硒57.2μg/kg及大量水溶性黑色素,还含一定量人体所需的铁和锌,是一个适于深加工的黑玉米新品种,又是天然优质高产饲草品种.栽培中应注意中耕培土防止倒伏,收获后及时脱粒晾晒防霉变。     

热处理对百合种球根螨防治效果的研究

带螨百合种球在38~42℃水中热处理1.0~5.0 h,观察其对根螨的防治效果及对后期生长发育的影响。结果表明,热水处理百合种球控制根螨效果显著。40℃是百合种球热处理除螨高温致死的临界点,40℃处理≥2.0 h,根螨致死率为100%;随温度升高处理时间缩短,但种球褐变率提高,热伤害加剧;39~41℃处理2.0 h,种球的发芽率和株高显著降低。因此,40℃处理2 h为百合种球除螨最佳处理积温。     

“920”浸种能提高红麻种子发芽率

正常年份,一般红麻种子发芽率是60—70％,如遇自然灾害,发芽率更低。1978年我省红麻收种期间,遇上近一个月的阴雨,果实不能晒干脱粒,不少种子在果内发霉,种子发芽率极低,经测定不同熟期的品种62个,发芽率在20％以下的44个,占70％,发芽率在21％以上的18个,占30％。     

甘薯氮磷钾肥施用的效应分析

在田间条件下研究了氮磷钾不同组配量对甘薯产量、肥料利用率及经济效益的影响。试验结果表明：氮、钾肥当季利用率随着施肥量增加而减少,平均为25．1％、29．5％。磷肥当季利用率呈无规律变化,其值在负值～24.3％之间;施氮区和施钾区都比缺氮区和缺钾区有较好的增产效果。氮、钾肥的增产效果依低、中、高施肥水平分别为：87．4kg、41．6kg、25．5kg和46．3kg、24．4kg、15．1kg。在土壤有效磷含量低时磷肥的增产效果明显,有效磷含量高时增产不明显;由回归方程得出最高施肥量为施N9．1～19．4kg／666．7m^2、P2O52．6-4．2kg／666．7m^2、K2O7．4-25．7kg／666．7m^2,最佳施肥量为施N8．4～17．4kg／666．7m^2、P2O52．3-4．2kg／666．7m^2、K206．1-24．2kg／666．7m^2。     

不同氮肥施用对杂交稻产量及其氮素利用效率的影响

为了探讨氮肥施用量和施用方法对杂交稻产量和氮素利用效率的影响,2001～2003年在湖南省宁乡县回龙铺镇进行了大田栽培试验。结果表明：改进施氮处理的氮肥用量为100～120kg／hm^2,比农民习惯施肥减少38．9％～47．6%,产量增加0．48～1．48t／hm^2,增幅6．32％～27．3％,减氮增产的效果显著;获得最高产量的适宜氮肥用量为99～147．5kg／hm^2,成熟期氮素吸收量为146．9～194．3kg／hm^2。改进的施氮处理AEN平均为10．6～14．3kg／kg．比农民习惯施肥增加7．0～10．7kg／kg;PFPN平均为65．2～96．8kg／kg,比农民的习惯施肥增加34．1～65．7kg／kg;REN平均为68．5％～76．2％,比农民习惯施肥增加14．1％～21．8％,增幅均达到显著或极显著水平。分析了氮肥用量对植株干物质在茎秆、叶片和稻穗分配的影响,讨论了植株后期对氮素的奢侈吸收而导致减产的可能性。     

“920”浸种能提高红麻种子发芽率

正常年份，一般红麻种子发芽率是60-70％，如遇自然灾害，发芽率更低。1978年我省红麻收种期间，遇上近一个月的阴雨，果实不能晒干脱粒，不少种子在果内发霉，种子发芽率极低，经测定不同熟期的品种62个，发芽率在20％以下的44个，占70％，发芽率在21％以上的18个，占30％。     

Seed quality as affected by nitrogen during true potato seed production and moisture conditions during storage

The objective was to investigate the effects of moisture conditions in storage at 21 C (± 3) on true potato seed (TPS) germination and seedling vigor. The influence of supplemental nitrogen (N) during seed production on these effects was also studied. One set of TPS was stored exposed to ambient humid (> 80% RH) air; the other was stored dry (sealed with silica gel). Germination tests were performed at 7, 11, and 14 months of seed storage. Seedling vigor tests were made at 14, 20, and 23 months. The rate of germination was mostly affected by the moisture conditions during storage. Seed stored dry germinated faster than TPS stored in humid ambient air. The rate of germination increased with time in storage and the percentage of germination was always high (≥ 95%) in dry seed produced with high N. Seedling vigor was mostly affected by N treatments during seed production. High-N seed had a much higher rate and percentage of emergence and seedling dry-weight levels than low-N seed, particularly when stored dry. Seedling vigor criteria decreased with time in storage in low-N seed; in high-N seed, the rate of emergence increased and the percentage of emergence was always high (≥ 95%). In conclusion, the TPS should be produced with high N and stored dry for sowing under unfavorable conditions.     

THE VIABILITY OVER A PERIOD OF FIFTEEN YEARS OF SEVERELY DRIED RYEGRASS SEED

Perennial ryegrass seed was dried at temperatures from 50°C to 120°C, the increases of 10°C being made regularly at intervals of 3 hours. The figures for germination capacity obtained immediately after treatment indicated that a lethal zone had been reached with final temperatures above 100°C and moisture contents reduced to 0.09 and 0.00 per cent.
It was shown that heat drying to as low as 0.66 per cent moisture at a final temperature of 100°C for 3 hours does not injure the germination capacity over a period of seven years, but after 15 years a greater loss in viability appears than in seed treated less severely. Germination energy figures (6-days' test) rather than germination capacity are a more reliable guide to optimum temperatures, duration of heating, and moisture content in the drying of seed for long-period storage.
The most favourable treatment in this series was found to be heating the seed gradually to a maximum temperature of 90°C for 3 hours with a reduction of moisture content to 1.62 per cent. Seed thus treated showed 81 per cent germination after 15 years; for the last eight years the bottles were stored in a cold room, after replacing the air in them with nitrogen.     

贮藏方法对花生发芽和出苗的影响

在恒温箱和田间条件下,研究了冰柜和陶缸两种贮藏方法对珍珠豆型、普通型、龙生型3种不同类型花生发芽和出苗的影响。结果表明：与当季收获的花生相比,两种贮藏方法的种子活力和出苗率均有不同程度的降低,冰柜保存的下降程度相对较低。方差分析表明,冰柜保存花生种子的发芽率、发芽指数和活力指数与对照相比差异不显著,而陶缸保存与对照相比差异达极显著水平,说明冰柜保存可以较好地保持种子活力。     

杂交水稻种子的裂颖及其危害

杂交水稻种子存在较严重的裂颖现象,这是不育系的一种遗传特性。裂颖种子不耐储藏,随储藏时间的延长,裂颖种子的生活力迅速衰退,发芽率和发芽势降低,秧苗素质差,并严重影响自然混合种子群体的发芽及幼苗生长。选育闭颖能力强的不育系,改进制种技术,强化种子选种,采用多起多落浸种和旱育秧等措施可防治或减轻裂颖种子的危害。     

Seed set with potato pollen stored at low temperatures

Pollen from several tuber-bearingSolarium species was exposed to liquid nitrogen (LN₂) and tested forin vitro germination and seed set capabilities. Pollen placed in LN₂ or in the vapor phase above LN₂ retained high levels ofin vitro germination after 11 to 24 months of storage. This pollen also set significant numbers of seed. Brief drying of the pollen over anhydrous CaCl₂ prior to freezing increased survival in most samples. Rehydration of dried, LN₂ treated pollen prior toin vitro germination testing was necessary to obtain maximum germination percentages. Rehydration, however, was not necessary for seed set, and in several samples decreased seed set compared to pollen that was not rehydrated. Storage of pollen from tuber-bearingSolanum species in LN₂ appears to be practical for maintaining pollen for crossing and for germplasm preservation.     

DRYING AND CONDITIONING OF DIRECT-HARVESTED TIMOTHY SEED

Germination results are presented for S48 timothy seed dried at air temperatures of from 75 to 135° after direct harvesting at 3 moisture levels, followed by cold-air conditioning for periods of from 1 to 3 days. The effect of conditioning was to increase the resistance of the seed to high drying-air temperatures, without producing any real improvement at low temperatures.
The results for non-conditioned seed, published earlier, are converted to simple chart form giving the limits of initial moisture content and drying-air temperature for 90% germination. These charts can be used during the final drying of conditioned seed, provided that the original moisture content at harvest is within the "safe" range.     

水合──脱水处理对杂交油菜种子活力的影响

自然老化和人工加速老化的杂交油菜种子经过水合—脱水处理以后，其活力和发芽率有显著捉高。主要表现在生理生化指标有明显改善，种子的电导率、糖分浸出量均比对照明显降低，脂肪酸活性显著降低．但脱氢酶活性有所提高．种子的类脂过氧化反应明显减轻。在水合—脱水处理中．以水分个衡—浸泡—脱水处理效果最佳。     

THE EFFECTS OF LONG-TERM STORAGE ON THE VIABILITY OF S23 PERENNIAL RYEGRASS SEED AND ON SUBSEQUENT PLANT DEVELOPMENT

Eight lots of seed of S23 perennial ryegrass which had been artificially dried to different moisture levels and stored for 20 years were tested for germinating capacity, and the effects of long-term storage on subsequent plant development were studied. The results of the germination tests indicated a continuation of the downward trend in viability previously reported. Observations on the derived mature plants revealed no difference between lots in general growth habit; a few seedlings showed symptoms of some retardation in growth but most plants manifested the high tillering and prostrate growth typical of S23 perennial ryegrass. Pollen fertility was markedly reduced in 38% of all the plants sampled. The seed-setting capacity was affected to an even greater extent, 44% of the plants giving seed-set values decidedly below those obtained for plants grown from new seed. Where pollen fertility had been much reduced, seed-setting also was usually low, but there were some instances of satisfactory pollen fertility associated with a low seed set.     

The effects of density, date of inflorescence emergence, date of harvesting and temperature upon seed quality in tetraploid hybrid ryegrasses

Thousand-seed weight, germination and seedling dry weight were measured in some tetraploid hybrid ryegrasses to study variations in seed quality. In cv. Sabrina, seed from spaced plants had a higher 1000-seed weight and seedling dry weight, and a slower germination rate than seed from narrow drills. Seed from later emerging groups of inflorescences had a low 1000-seed weight and seedling dry weight, but a high germination rate. Seeds of cv. Sabrina, Leri and Augusta harvested at between 10 and 25 d after peak anthesis had low 1000-seed weights, low germination rates and low seedling dry weights. Air temperatures between inflorescence emergence and seed maturity also affected seed quality; an increase in temperature from a 15°/10°C regime to a constant 25°C environment reduced 1000-seed weight and seedling dry weight, but increased germination rate. It is concluded that year-to-year variation in seed characters will occur because of temperature and other climatic changes, but seed quality can also be influenced by the time at which the seed is harvested. If combine harvesting is carried out at a moisture concentration of about 400 g kg^-1 (≡40%) then maximum yields of seed of a high quality should be obtained.     

自由空气中CO_2浓度和温度增高对水稻种子活力的影响

大气二氧化碳(CO_2)浓度和气温增高是全球气候变化的重要特征,本研究旨在揭示未来气候变化条件下生长的水稻,其种子活力是否受这两个重要环境因子的影响。利用稻田FACE(Free Air CO_2Enrichment)系统,以常规水稻武运粳23为供试材料,设置对照(Ambient,环境空气)、CO_2浓度增高(比Ambient高200μmol/mol)、温度增高(比Ambient高2℃)和CO_2浓度与温度同时增高四个处理,成熟期收获种子进行实验室标准发芽实验。结果表明,与对照相比,单独CO_2浓度增加使成熟种子浸种24h浸出液电导率平均增加16.5%,但使种子露白率、发芽率、发芽势和发芽指数分别下降7.8%、10.0%、17.4%和8.9%。相似地,单独温度增高或CO_2浓度和温度同时增高处理对上述参数影响的方向一致,但影响的幅度变小,多未达显著水平。与环境生长温度相比,高温环境下全生育期CO_2浓度升高使成熟种子浸种24h浸出液电导率、露白率、发芽率、发芽势和发芽指数的影响变小,表现在CO_2浓度与温度处理间存在一定程度的交互作用。种子发芽后芽和根系性状对高CO_2浓度或高温均无显著响应。以上结果说明,大气CO_2浓度增高200μmol/mol环境条件下,常规粳稻武运粳23成熟种子露白率、发芽率、发芽势和发芽指数等指标均明显下降,但在同时适度增温的生长环境下这种负面影响有减弱的趋势。