Effects of Tillage and Fertilization on Some Selected Physical Properties of Soil (0–30 cm Depth) and on the Root Growth Dynamic of Winter Barley (Hordeum vulgare cv. Niki)

The root mass of winter barley ( Hordeum vulgare cv. Niki) at growth stages 5, 9 and 16 of the Feekes scale increased from 100 % (0.272 mg cm^–3 soil) to 132 % and 139 %, respectively. Root mass was always greater in no-tillage (NT) plots than in ploughed-tillage (CT) plots and was also greater where manure was applied in comparison to plots without manure. The root density at growth stages 5, 9 and 16 over all treatments was 0.197, 0.224 and 0.238 cm cm^–3 soil, respectively. At growth stage 5, the root density in NT plots was 9 % greater than that in CT plots, and in rotary hoed (MT) plots it was 3 % greater. At this same growth stage, soil fertilization with NP, farmyard manure (30 t ha⁻¹) and NP plus farmyard manure improved the root density of barley by up to 5, 10 and 11 %, respectively, in comparison with control plots. The diameter of barley roots was clearly biggest in CT plots, while in NT plots the thinnest roots were found. The mean diameter was 0.63, 0.75 and 0.78 mm at growth stages 5, 9 and 16, respectively (over all treatments). Significant correlation coefficients were found between root density (RD) and the soil properties bulk density (BD), porosity (P), penetration resistance (PR) and mean weight diameter of aggregates (MWD). For example, the highest r values were as follows: at growth stage 5, r=0.95 (P < 0.001) for P and r=0.86 (P < 0.001) for MWD; at growth stage 9, r=−0.97 (P < 0.001) for PR and r=0.96 (P < 0.001) for P, and finally at growth stage 16, r=0.97 (P < 0.001) for P and r=−0.97 (P < 0.001) for PR.     

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.     

Effect of Seeding Rate on Seed and Hay Yield in Common Vetch (Vicia sativa L.)

The effects of six seeding rates (50-300 seeds m^−2:) on some morphological traits with hay and seed yield were evaluated in common vetch ( Vicia sativa L.) under fall and spring sowing conditions. The mutual correlations among yield and yield components were also determined.
The sowing seasons and seeding rates significantly affected hay and seed yield, and most of the yield components. Fall sowings resulted in significantly higher hay and seed yield than spring sowings at all seeding rates, and the highest seed and hay yield was achieved in densities of 250 and 300 seeds m⁻². In spring sowings there was a positive response in hay yield up to 250 seeds m⁻² while no further increase in seed yield at the seeding rates higher than 150 seeds m⁻². Average protein content of hay and seed was found to be higher in spring sown crops than fall. The highest protein yields of hay and seed were obtained at 250 seeds m⁻² in fall sowings, and 150 seeds m⁻² in spring sowings.
Most of the correlations between both hay and seed yields with the yield components were not consistent and differed with the sowing time. Only the correlations between number of the plants per unit area with hay yield, and number of the pods and seeds per unit area with seed yield were statistically significant in both sowing seasons. Close positive associations were obtained between hay and seed yield.     

The Effect of Nitrogen Fertilization and Population Density of the Field Bean (Vicia faba L. minor) of Indeterminate and Determinate Growth Habit on the Symbiosis with Root Nodule Bacteria and on the Seed Yield

Field beans of indeterminate (cv. Nadwiślański) and determinate (cv. Tibo) growth habits were grown on field plots with a density of 20, 40 and 80 plants m⁻² at two levels of nitrogen fertilization: low (20 kg N ha⁻¹) and very high (150 kg N ha⁻¹). At the phase of intense pod growth the number and the dry matter weight of root nodules as well as their nitrogenase activity and some features of the plants growth were determined, and in the period of ripeness the components of seed yield were established.
It was found that increased density of sowing as well as the high level of nitrogen fertilization inhibited the growth and development of root nodules and limited their nitrogenase activity in both cultivars. Plants of both varieties were characterized by a similar potential of forming the root nodules, however, in plants of the cv. Tibo the nitrogenase activity of nodules was much lower than in the cv. Nadwiślański.
Increased population density of the plants has in both varieties given increased seed yield when calculated per m² of the soil, compensating in excess the depression of the seed yield from one plant. Such compensation did not occur in the case of the depression of nitrogen fixation under intense nitrogen fertilization.     

长期定位施肥对冬小麦叶面积指数及群体受光态势的影响

为了研究氮肥与有机肥配施对冬小麦群体的影响,揭示实现冬小麦高产的条件,试验分析了长期定位施肥条件对冬小麦的叶面积指数及受光态势的影响。结果表明:氮肥和有机肥的施用量越大,群体越繁茂,叶面积指数也就越大,而群体内部光照强度就会降低,表征群体受光态势的半消光深度与叶面积指数极显著负相关。叶面积指数与氮肥(N)和有机肥(M)施用量之间的关系:LAI=4.41×10-3N 5.93×10-5M 0.888,通过合理施肥可以创造出具有最适叶面积指数的冬小麦群体。     

Effect of Time of Harvest of Vetch (Vicia sativa L.) on Yields of Subsequent Barley in a Dry Mediterranean Environment

The introduction of annual feed legumes into the intensifying systems of barley monocropping in dry-area Mediterranean agriculture would reduce pest and disease risk and increase sustainable productivity. Potential modes of legume utilization by small ruminants — as green grazing, hay, or mature grain and straw — imply different times of harvest removal with possible consequences for the subsequent barley crop. In nine two-year trials, barley following green-grazed common vetch (Vicia sativa) always outyielded barley following vetch cut as hay or harvested at maturity, albeit in some years by small and non-significant margins; mean differences in barley grain and straw yields between green-graze and mature vetch treatments were around 20 %. The main mechanisms implicated are carryover to the barley of small amounts of soil water unused by early-harvested vetch and enhanced nitrogen availability where active vetch root systems were killed by removal of the above-ground crop.     

The Effect of Detopping the Field Bean Plants (Vicia faba L. minor) and Lack of the Pod Setting on the Symbiosis with Root Nodule Bacteria

The plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production.     

Effects of Row Spacing, Support Plant Species and Support Plant Mixture Ratio on Seed Yield and Yield Characteristics of Hungarian Vetch (Vicia pannonica Crantz)

The effects of row spacing (17.5 or 35.0 cm), support plant species (barley or triticale) and the proportion of crops in mixtures (no support plant or support plant 20, 40 or 60 %, respectively) on the seed yield and yield characteristics of Hungarian vetch (Vicia pannonica Crantz) were investigated. Increasing the row spacing increased the seed yield of V. pannonica from 881.0 to 1248.0 kg ha^?1. On average, in a pure stand the seed yield of V. pannonica was 1141.0 kg ha^?1. In mixtures with barley and triticale, the seed yield of V. pannonica averaged 986.0 and 1143.0 kg ha^?1, respectively. In single mixed stands the seed yield of V. pannonica varied between 551.0 kg ha^?1 (60 % support plant barley) and 1603.0 kg ha^?1 (20 % support plant triticale). The yield advantage of V. pannonica in this triticale mixture was 40 % compared to the V. pannonica pure stand. With respect to the total yield in the mixture with 20 % triticale (1902.0 kg ha^?1) the yield advantage over the V. pannonica pure stand was as high as 65.1 %. In the mixed stands the number of seeds per pod and the thousand‐seed weight of V. pannonica were higher than in V. pannonica pure stands.     

寒地保护性耕作栽培技术对水稻产量及产量构成的影响

采用留茬带状分层旋耕、苗带全层施肥、免除水整地的保护性耕作方法,研究了寒地保护性耕作栽培技术对水稻产量及产量构成的影响。结果表明,保护性耕作高产群体平均产量为8467.54kg/hm2,比常规耕作增产3.0%,且在总肥料为509.7kg/hm2时,最有利于增产;保护性耕作结实率和千粒重均小于常规耕作,是由于单位面积穗数和穗粒数高的负相关造成的;单位面积穗数和穗粒数的增加,是水稻保护性耕作增产的主要原因。     

Genetic control of somatic embryogenesis in alfalfa (Medicago sativa L. cv. Adriana)

Summary In alfalfa (Medicago sativa) regeneration is genotype-specific. In order to study the genetic control of somatic embryogenesis and to constitute a synthetic cultivar characterized by its high regeneration ability, 2 embryogenic plants selected from the cv. Adriana were selfed, intercrossed and also crossed in both directions with 5 non-embryogenic genotypes of the same cultivar.Progenies of all crosses were scored for their regeneration ability and results indicate that somatic embryogenesis is under the control of 2 dominant loci. However some non-embryogenic genotypes prevent regeneration when crossed with embryogenic ones and this characteristic is not under the control of a single dominant gene.When plants chosen for their capacity to regenerate within F₁ and S₁ progenies were freely intercrossed the regeneration efficiency dropped to 2% (1 plant out of 50). This result indicates that if the genetic background of the population is changed the regeneration is greatly affected and therefore some other mechanism could play a role in determining plant regeneration.     

耕作与保墒措施对小麦不同生育阶段水分利用及产量的影响

为探明不同耕作与保墒措施下冬小麦不同生育阶段的水分利用特征,采用田间试验,研究了普通耕作、深松、秸秆覆盖、保水剂、有机肥等措施对小麦不同生育阶段的耗水量、干物质积累量、水分利用及产量等的影响。结果表明,在小麦不同生育阶段均以秸秆覆盖和深松处理的保墒、储水效果较佳。在小麦整个生育期中,有机肥处理的耗水量最大,而深松和秸秆覆盖处理较少。在小麦拔节期前,有机肥处理更利于干物质的积累;在小麦拔节-孕穗期,以保水剂和深松处理积累的干物质量较高。孕穗期以后,秸秆覆盖处理的干物质积累量均高于其他处理,且秸秆覆盖处理在小麦全生育期的干物质积累量也较高。除返青-拔节期和孕穗-扬花期外,小麦不同生育阶段的水分利用效率均以秸秆覆盖处理最高,且其产量和水分生产效率均高于其他处理,其产量较普通耕作提高了50.9%,水分生产效率提高了11.7 kg/(mm·hm~2)。综上所述,秸秆覆盖处理较其他措施更能有效地改善小麦不同生育阶段的水分环境,从而促进小麦产量和水分利用率的提高。     

Pollination, Fertilization and Seed Development in Inbred Lines and F1 Hybrids of Spring Faba Beans (Vicia faba L.)

When the flowers are not disturbed, the yield of F₁ hybrids of faba beans normally exceeds that in their inbred parents. The basis of this “heterotic autofertility” was investigated by examining flowers for pollination and fertilization throughout the flowering season and assessing the distribution of seeds and pods on mature plants. Six inbred lines and seven of their F₁ hybrids were grown without protection from bee visitation, and their autofertility was estimated’ by comparing their fertilization with that of cytoplasmic male-sterile line. The first direct evidence was obtained that heterotic autofertility acts by increasing; the proportion of flowers which were pollinated and fertilized. The autofertility was not perfect, especially in a closed-flower hybrid, as many ovules remained unfertilized. Several factors contributed to the number of seeds per pod in F₁ hybrids, being superior to parental means: (1) more ovules per flower, (2) greater fertilization of the basal ovules, (3) reduced abortion of the apical ovules and (4) greater overall maturation ovules.     

Effects of Soil Drought in the Generative Phase of Development of Field Bean (Vicia faba L. var. minor) on Leaf Water Status, Photosynthesis Rate and Biomass Growth

The effects of 10-day periods of soil drought during flowering (DI) or pod growth (DII) and during both these phases (DI + DII) on leaf water status, photosynthesis rate, plant growth and production of biomass was studied in pot experiments with field bean. Soil water content during drought spells were kept at 30% of field water capacity. Soil water deficiency DI and DII depressed the leaf water potential relatively to control by about 100 % and 140 % respectively, increased the water deficit by 100 % and 120 % and reduced photosynthesis rate by 80 % and 90 %. Rehydration of tissues completely abolished any decline of photosynthesis rate caused by drought DI, but after drought DII photosynthesis rate remained depressed by about 30 % even after rehydration. Drought periods DI and DII caused more rapid withering of leaves, a decline in the total leaf area and a temporary increase of root weight.
Drought occuring at flowering (DI) also activated the mechanism of plant adaptation to water deficiency during the pod formation phase (DII). Single or double periods of drought had not any significant influence on the number of pods and seeds, but decreased their weight.     

ipt基因表达及外源细胞分裂素对油菜幼苗侧根发育的影响

通过对转ipt基因油菜(Brassica napus L.)及野生型油菜种子的发芽培养,研究了ipt基因的表达及外源细胞分裂素对油菜种子幼苗侧根发育的影响。结果表明:ipt基因表达和高浓度的外源细胞分裂素对油菜幼苗主根长度、侧根原基的起始及侧根的发生均表现出明显的抑制作用。当KT和6-BA浓度达到1mg/L时,侧根的发生被完全抑制,外源生长素IBA可以缓解ipt基因超量表达对油菜种子侧根发育的抑制作用。     

赤峰地区敖汉苜蓿冻害及其防御技术

敖汉苜蓿在赤峰地区受冻有4种表现,（1）全株未受冻;（2）根颈上端受冻变黑,下端仍能再生新芽;（3）根颈全部和根的部分受冻变黑,不能再生新芽;（4）全株受冻死亡。引起冻害的主要原因是苜蓿播种期晚和根颈入土浅。研究结果表明,越冬前芷蓿具有2个以上分枝,根颈入土深度5cm以上,以及根颈膨大,直径达0．3cm以上者,方能减轻或避免受冻。适时早播或带肥播种,延长苜蓿生长期和促进幼苗生长,同时在封冻前对平作进行浅耕覆土或深开沟冻磨平,无能增加根颈保温层,有效提高苜蓿越冬率。     

Effect of Shading on Nodule Growth and Sugar Distrihution in Faha Bean (Vicia Faba L.)

The faba bean ( Vicia faba L.) is an important grain legume world wide, yet the relationship between light intensity and nodule development and N₂ fixation has received minimal attention. An experiment was conducted to study the effects of shading on faba bean growth, seed yield, nodule development, and the distribution of total N and total sugar among plant parts. Seeds of the V. faba cultivar Xichang Dabai were sown in pots at Xichang. China, in 1986–90. The plants subjected to 50 % and 20 % shading for 145 d had thinner and taller main stem than the control, and fewer flowers, pods, and seeds. Poor dry weight of organs and less developed underground parts were recognized. Shading caused the deficiency of photosynthate (supply), subsequently less nodules formed poorer fresh weight of nodules was produced and nodule senescing advanced. Total N and total sugar contents per plant and in roots, stems and leaves were consistently lower under shading regimes, but the contents in nodules did not change significantly. It seems that the insufficient photosynthate supply limited both N and C metabolism in shading plants by first limiting growth of the whole plant and nodule, and that the lower total N content in faba bean plant under shading regime was attributed to an decreased effective nodule mass and advanced nodule senescing.     

不同耕作措施对麦田土壤碳储量和作物水氮利用效率的影响

为了探索耕作措施和秸秆还田对麦田土壤碳氮水的动态变化的影响,在田间定位试验的基础上,通过深耕(T1)、深耕+秸秆还田(T2)、浅耕(T3)、浅耕+秸秆还田(T4)4种不同耕作方式处理,对麦田碳储量、土壤含水量、全氮含量以及作物水氮利用效率的变化进行了研究。结果表明,秸秆还田在不同时期对土壤碳储量有一定的影响,与播前土壤有机碳储量相比,0~20 cm土层各处理在越冬期有较高的有机碳储量,20~40 cm土层则于拔节期有机碳储量达到最大值,40~60 cm土层除T1处理,其他处理皆为拔节期最大。综合来看,在整个生育期有机碳储量均表现为秸秆还田处理大于秸秆不还田处理。深耕处理提高了小麦生育前期的土壤含水量,T2处理的作物耗水量比T4处理高4.2%;秸秆还田提高了作物的水分利用效率,T2的水分利用效率、灌溉水利用效率分别比浅耕加秸秆还田高24.9%,27.6%。除开花期,T1处理的植株含氮量高于浅耕处理,T2处理能够显著提高冬小麦氮素积累量,较不还田处理提高了44%;T1处理的氮素利用效率比浅耕处理高57.2%。秸秆还田处理在生育前期抑制了小麦的生长,但后期促进了植株干物质量的积累。秸秆还田有利于穗粒数的提高,从而提高产量,T2处理较T3处理产量提高了22.1%,较T1处理增产6.7%;T1处理较T3处理增产14.4%。因此,秸秆还田和深耕有助于提高土壤碳储量,提高水分和氮素利用效率,进而提高作物产量。     

不同保墒耕作措施对小麦、玉米耗水特征及周年水分利用的影响

为探明土壤结构改良与保墒耕作措施对小麦、玉米周年水分利用的作用机制。采用田间试验,研究了常规耕作、秸秆还田、保水剂、有机肥、免耕、深松、深松+秸秆覆盖等措施对小麦、玉米生长过程中的耗水特征、光合特征及周年水分利用的影响。结果表明:深松+秸秆覆盖在小麦生育期内储水量较高。从小麦播种-返青期,深松+秸秆覆盖处理的耗水量最低。而在返青-拔节期,该处理最大,而其在孕穗-抽穗期的耗水量却最低。在拔节-孕穗期,保水剂处理的耗水量最大,而在抽穗-灌浆期,其耗水量最小。在灌浆-收获期,秸秆还田和保水剂处理的耗水量较其他处理低。在玉米整个生育期内,保水剂和免耕处理的耗水量较其他处理低。不同措施改善了小麦和玉米的光合生理特征,促进了小麦、玉米产量和水分利用率的提高。各处理中,以免耕处理的小麦产量和水分生产效率最高,分布较常规耕作提高了18.3%和20.0%。以秸秆还田处理的玉米产量和水分生产效率最高,分别较常规耕作提高了21.6%和23.8%。而深松处理的小麦-玉米复合产量最高,其次为免耕处理,其分别较常规耕作处理增产14.9%和14.3%。而深松+秸秆覆盖处理和免耕处理的总水分生产效率较其他处理高,分别较常规耕作处理提高了18.5%和18.1%。说明深松和免耕处理更利于小麦、玉米周年节水增产。     

Some Effects of Soil Salinity on Growth, Development and Yield of Rapeseed (Brassica napus L.)

The effects of increasing soil-salt levels on emergence, shoot and root growth and yield composition of rapeseed were investigated. A range of electrical conductivity (EC) values in the soil solution from 2.3 dS m^-1 to 10.3 dS m^-1 was obtained by adding NaCl to the substrate. The emergence was significantly (P < 0.05) decreased at EC values higher than 6 dS m^-1 Above this value, a delay in the appearance of leaves and of the first visible internode was observed. The further increase of salinity level extended the period for siliqua formation and grain filling, and plant height, pod number and grain number per plant were lowered. However, the cultivar used showed the ability of counterbalancing for this lower grain number by increasing the seed weight, thus there were no variations on seed yield. The seed oil and protein content were also not affected by the changes in salinity. Root growth was adversely affected when salinity levels exceeded 6 dS m^-1. Beyond this value, short tuber-like roots became remarkably frequent. This may be an adaptation mechanism of this species to saline stress; a similar reaction in rapeseed is known in adaptation to drought stress.     

Callus Formation and Plant Regeneration from Protoplasts Derived from Suspension Culture of Rice (Oryza sativa L. cv. 'Taipei 177')

Protoplasts were isolated from young inflorescence-derived suspension cultures of a japonica rice cultivar ‘Taipei 177’. The isolated protoplasts which were cultured either in liquid, agar on Sea plaque agarose underwent sustained division. Maximum plating efficiency of 1.06% occurred in a medium containing macroelements of KM, microelements and vitamins of B5, 0.5 % Sea plaque agarose, 1.0 mg/l of 2,4-D, and glucose as an osmotic stabilizer. Green and albino plants were regenerated from the protocalli in MS semisolid medium containing 4 mg/l BAP, 0.5 mg/l NAA and 500 mg/l casein hydrolysate (MS_18–2).