摘要:

AbstractDynamics of inorganic soil nitrogen during spring and its importance for N‐fertilizer management in cultivation of sugar beetsHigh sugar yield depends very much upon application of the correct dose of nitrogen fertilizer. To determine fertilizer needs in sugar beet cultivation two methods – Nminand EUF – are discussed at present. Both methods are criticized not to be able to take into account the amount of soil nitrogen which becomes available between the early date of soil analysis and actual nutrient uptake in the sugar beet stands.The objective of this study was to investigate the influence of varying N‐mineralisation rates on growth and yield of sugar beets and corresponding changes in N‐fertilizer requirements.The differences in soil nitrate content in February showed no relation to the amount on N available during the early vegetation period. Therefore very low correlation coefficients were observed between soil nitrate content in early spring (February/March) and sugar yield (R2>0.2). However highly significant correlation coefficients were obtained for NO3‐N‐content in April/May in the 0—60 cm soil layer and sugar yield (R2= 0.62—0.78). Maximum sugar yield was obtained with 220 kg N/ha soil nitrat content in April/May in 0—‐60 cm. A wide N‐optimum range for maximal sugar yield was observed. Deviations less than 50 kg N/ha from the optimal N amount caused no significant changes in sugar yield.Higher amounts of late available nitrogen deposited at greater soil depths caused a decrease in sugar content and an increase in alpha‐amino‐N and sodium. Early applications of nitrogen fertilizer (before sowing) are endangered to be leached to lower depths with heavy rain falls and therefore may cause detrimental effects on juice purity and sugar content. For obtaining maximal sugar yield it is recommended to apply N‐fertilizer 1 or 2 weeks after and not before seeding.Related to the wide optimum of N‐requirement ist seems possible to determine the use of Nitrogen fertilizer according to local experience. In special cases (slurry, tillage of wet soils, preceeding vegetables or legumes) it is suggested to determine NO3‐N‐content in April (0—60 cm) and to apply nitrogen fe

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00001.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA field experiment was conducted at the Livestock Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar, India during the wet season (June—October) of 1980 with the objectives of characterizing the seasonal changes inin vivonitrate reductase activity (NRA) and N contents of upland rice cultivars grown under rainfed condition at low (0 kg N/ha) and optimum (80 kg N/ha) N fertility.In vivoNRA increased initially up to panicle initiation stage (50 days after sowing) and declined, thereafter, until 90 days. Leaf NO3‐N content paralleled within vivoNRA throughout crop season. Total N content of leaves and stem declined with advance in crop age, whereas panicle N content increased with the crop development. Optimum N fertility (80 kg N/ha) always resulted in higher NRA, NO−3and total N contents of rice p

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00002.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA diallel analysis to identify parental lines and specific crosses through combining ability estimation was undertaken in a set of seven rice varieties. Griffing'sMethod I, Model I was employed for this purpose. The seven parents and 42 F1s (including reciprocals) were grown in a randomized block design with four replications. Data were collected on 16 characters including a few root characters for which requisite number of plants were grown (in RBD design) in pot culture.GCA and SCA variances were significant for all the characters. Reciprocal effects were also significant except for rachilla/panicle and grain length. An early flowering NC 1281 Mutant and Taichung Native 1: bold grain mutant were good general combiners for majority of characters. The crosses with high specific combining ability generally involved high × low general combiners. The cross Nira × T‐N‐1: bold grain mutant recorded best SCA effects for grain yield as well as all the important yield attributes and also for major root characters. In fact, in most of the high SCA registering crosses for various characters, Taichung Native 1: bold grain mutant or Nira was one of the parents commonly inv

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00003.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractCompensation capacity of wheat ears depending on temperature level during grain‐filling periodIn order to investigate the compensation capacity, effects of sterilization treatments on dry matter storage within spikelets and florets of wheat ears, growing in different temperatures during grain‐filling period were tested. Alternatively proximal or distal florets from 6 spikelets in the central region were removed at different stages. — Grain weight/ear remained 40% smaller in the high compared with the low temperature level. With high temperature sterilization of proximal florets allowed more additional florets in distal positions to develop grains than with low temperature. Beyond of this in both levels single grain weights in the basal and the apical region of the ear increased. Compensation effects, especially by additional grains decreased as later the treatments were done. Relatively the grain weight loss by sterilization was compensated to a higher degree in high than in low tempera

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00004.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA 1‐year study was conducted in 1983/84 at 2 experimental sites in Brazil to determine the effect ofAzollagreen‐manure (AO),A.intercrop (OA) and their combination (AA) on rice yield in comparison to mineral fertilization with urea. Nitrogen sources were combined with 4 rice sowing/planting systems.On terraced terra‐roxa soil (Paleudalf) in subtropical northern Paraná State, transplanted rice (T) yielded 8.66 t · ha−1compared to pregerminated (P), direct‐sown (D) and conventionally sown (C) rice with 7.92; 7.73 and 7.48 t · ha−1, respectively. N‐source treatments yielded 9.33; 8.54 and 7.34 t · ha−1for AA, OA and AO compared to 8.46; 7.98 and 6.05 for 100, 50 and 0 kg N · ha−1, respectively. Fertilizer‐nitrogen equivalence (FNE) ofAzollatreatments compared to urea broadcast in 3 applications ranged between 0 and more than 100 kg N · ha−1.On hydromorphic latosol (Ustic Dystropept) in tropical Goiás State, rice yields were 4.07; 2.52; 1.46 and. 1.33 t · ha−1for systems T, P, C and D, respectively. N‐source treatments yielded 2.79; 1.98 and 1.78 t · ha−1for AA, AO and OA compared to 3.43; 2.63 and 1.46 t · ha−1for 60; 30 and 0 kg N · ha−1as urea broadcast in 2 applications, respectively. FN

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00005.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThere is a large area of acid lateritic soils (Acrorthox) around Kharagpur in the state of West Bengal, India, where the top thin layer of soil mostly of detrital material, is underlain by a deep and highly porous lateritic crust (burried). Management of these soils poses a problem for their exceedingly high permeable nature. With the objective of increasing the production of rice in lateritic tract by way of reducing deep percolation, artificially compaction with the help of roller (800 kg) at the surface and subsurface levels were introduced under field conditions. Results indicate that the 6 passes of roller reduced the percolation by more than 3 folds over control. The increase in percolation rate with tillage depth was associated with the change in pore geometry obtained by tillage. The percentage increase in grain yield over the control was about 37 per cent at 4 passes of compaction, the increase was attributed to the reduction of deep percolation losses. The decrease in yield at high level (6 passes) compaction may be attributed to increased mechanical impedence and reduced condition (low Eh) in the compacted soil. Yield of rice has increased significantly with tillage depths at high level (6 passes) compaction probably due to increased root penetration.

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00006.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractWinter rape plants vernalized under natural conditions were used as stock for grafting apical and subapical parts of rape seedlings vernalized at 5 °C in light during different periods ranging from 0 to 10 weeks. Acceleration of generative development in both kinds of grafts occurred already after 3 weeks of their vernalization, i.e. after cold treatment of insufficient length to induce flowering in plants developing independently. Effectiveness of vernalization — measured by acceleration of flowering in grafts was highest from 3rd to 5th week of cold treatment and then it declined. Processes occurring during an early stage of vernalization, though insufficient to allow independent generative development, become manifest in grafts made on vernalized stock. This allows investigations of very early stages of vernalization processes inaccessible to observation by other metho

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00007.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractEffect of field bean and soybean cultivation on soil compaction amelioration and its influence on wheat and barley as subsequent cropsAmelioration effect of field bean and soybean growth on compacted soil and its influence on the following crops of wheat and barley was tested. The performance of both field bean and soybean was affected by compaction. A reduction of 5–16 % in total dry matter, 10–22 % in seed yield, 5–12 % in no. of pods per plant, 4–14 % in plant height, 8–19 % in total accumulated N in plant and 11–22 % in accumulated N in seed of the both crops was registered. The crops were grown at 30 and 60 plants/m2densities. The negative effects of compaction were compensated to some extent by high plant density. Both crops loosened the compacted field, the effect increased with an increase in plant density. Field beans decreased the soil bulk density up to 8 %, increased total porosity up to 8 % and air filled pores up to 19 % till 30 cm soil depth, the effects being higher than produced by soybeans.The increases in yields of wheat and barley and in their accumulated N were 9–57 % and 11–56 %, respectively after field bean and soybean as preceeding crops th

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00008.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractUsing grain‐material of 12 field bean (Vicia faba) varieties from three quite different locations 10 different constituents and their range were examined and the following results obtained:1In the case of N‐, P‐, and K‐contents significant differences between the varieties and genotypes can be noticed. The average values obtained are 4.97, 0.63 and 1.33 % respectively.2Field beans have a relatively high Fe‐ and Zn‐content with an average of 61.1 respectively 40.1 ppm, whereas the average value of Mn and Cu was only 16.0 respectively 12.6 ppm.3As far as starch, crude fat and crude protein are concerned, great differences can be observed. The average values were 42.97, 1.83 and 31.06 %. However, significant differences were noticed between the varieties and th

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00009.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY