Iranian Journal of Crop Sciences
Year:2000 | Volume:2 | Issue:4|Papers Count:9

With the objective of investigating the time of nitrogen(N) application and the beet combination of base vs. top dressing basal N/top dressing N application on some sugar beet characteristics this experiment was carried out in 1994, karaj - Iran. Experimental design was split plot within Randomize Complete Block with three replications. Four level of split N was applied (100% top dressing- 25% base, 75% top dressing - 50% base, 50%top dressing - 75% base - 25% top dressing) as the main plot and time of N application (planting time, 2-4 leaf stage, 8-10 leaf stage) as sub plots. Amount of N used in all the treatments was the same and equal to 138 kg/hectar. After 53 days from planting and receiving 824 degree days samples were taken and continued every 15 days intervals. The results showed that the time of N application influenced the amount of Na+ and α Amino - N. It was also shown that delay in time of N application increased the Na+ and α - Amino-N but did not effect amount of K+. The time of N - consumption affected on root impurties. S.c. was effected by N consumption in growth period. But, the results showed that there were no difference among N treatment with respect of sugar content.

The present study was conducted with using split plot in a factorial design with three replications for two years from 1994 to 1996.The main factor was harvesting date with five levels started from 6th of Aug continued in a 15 days intervals and subplots were pre-germination at two levels (germinated or not germinated) and cultivars at three levels (Aula, Deraga & Kaiser). Pre-germination was achieved within one month, in a controlled environment conditions of required light intensity and temperature of 15-20 °C. The analysis of multiple variance was run and results showed that pre-germination positively influenced the number of stem in plants, date of germination, harvesting and lubrication which was significant at the 1% level. Date of harvest only affected the number of tubers per plant and this affect was significant at the 1% level. There was a significant difference amoung cultivars for recorded characteristics. Comparison between means indicated that the productivity of cv. Draga was significantly higher (32130 kg/ha) than the two others(Kaiser with 29930 kg/ha and Aula 29580 kg/ha) and this classified the former into a different class than the two later cultivars. There was a significant two way interaction between cultivarsand pre -germination, indicating that Kaiser and Aula responsed positively to pre-germination where as this was detrimental for Draga. Comparison of correlation coefficients showed that there were significant positive correlation between yield and above mentioned characteristics. In conclusion least past harvest lossen, despite a negative inconclusion, the cv. Draga with highest productively, least post-harvest Losses, despite a negative response to pre-sprouting, is recommends for Ardebil provence in Iran.

This study was carried out in 1996 in orther to compare yield and other traits in rice cultivars under direct seeding and transplanting methods at Joneghan region of Chaharmahal and Bakhteyari province. Genotypes were composed of three selected lines (4 ,30 and 65) from local breeding populations, varieties 24IRCTN90 and Gerdeh Joneghan local variety. In this investigation 2 factors were compared in a factorial experiment with 3 replications. One factor consisted of 5 lines and cultivars and another factor consisted of 2 planting methods. Planting time in both the direct seeding and transplanting methods were the same. Harvest time both in this experiment and in the region was also the same. Results indicated that all cultivars had lower yield than local variety under direct seeding method and their growing period could be not completed. The yield under transplanting was higher than direct seeding method in all of the cultivars. Line 65 showed the highest yield (54ookg/ha) under transplanting method. In direct seeding, the performance of other traits was significantly less than transplanting method.

This experiment was carried out to determine the best time of using nitrogen fertilizer and study the interaction between fertilizer and bacteria in soybean on Williams cultivar. The statistic design in this study was split plot designs with three replications where factor A was fertilizer treatment in five levels and factor B was bacterial treatment in two levels. During growth season characters such as seed yield, pod yield, leaf area index, 100 - seed weight and harvest index were measured on ten random plants. The results of the experiment indicated that inoculating the soybeans seeds with bacteria increase the plant growth. Treatments with or without the bacteria showed significant differences. The best fertilizer treatment for seed and fodder production was determined by analysis of variance. The results of this experiment indicated that fertilizer treatments had significant differences with respect to seed and fodder production. The fodder production in the second treatment and seed production in the fourth treatment was higher than the others respective treatment. So it is suggested that for seed production the fourth fertilizer treatment and for fodder prodution the second fertilizer respective treatment be used.

In order to determine the effect of plant density, different ratios of Barley and Bersem clover, effect of method of planting on forage quantity & quality, a series of experiments were conducted in Ahvaz, Iran, during 1993, 1995 and 1997. In 1993 the following factors were studied; three levels of density (optimum local density and two other densities equal to half & twice of optimum), planting ratios in five levels (Barley and Clover pure stand, mmures of 75% Barley +25% Clover; 50% Barley + 50% Clover and 25% Barley + 75% Clover) with replacement series technique. An ANOVA indicated significant dry forage differences between densities and planting ratios (p = 99%). D3R3 treatment (mixture of 50:50 in high density), with 10.32 t/ha dry matter and 1923 kh/ha crude protein produced maximum yield. In 1995, first the experiment included three levels of density with row intercropping (common local practice density and two others equal to 1.5 and twice of common density) and planting ratios in five level (the same as previous experiment). Analysis of variance indicated significant differences in dry forage between densities and planting components (p = 99%). D2R3 treatment (50:50 in medium density), with 12.41 t/ha dry matter and 1850 kg/ha crude protein produced maximum yield. Calculated "LER" indicated that 24% dry matter and 30% crude protein more than pure. Second experiment had three levels with mix intercropping the local density practice and two other equal 1,5 and twice of the common density) and planting ratios in five levels. The experiment was designed in factorial arrangement such that (D2R4) treatment (mixture of 25% Barley + 75% Clover in medium density). with 16.801 t/ha dry matter and (D1R4) sole barley in low density with 4.744 t/ha dry matter produced maximum and minimum yield receptivity. (D2R4) produced crude protein equal to 2813 kg/ha and crude fiber was 27.53% which was the most suitable mixture. In 1997 experiment the factors were methods of planting with two levels (row and mixed planting) and proportions of planting, similar to the previous experiment. With respect to the results of previous experiments, the plant density was 1.5 times of the conventional density for both crops. Generally there were high significant differences between methods, proportions, and their interactions (P = 99%). The D2R4 treatment (mixed inter cropping of 25% Barley + 75% Clover), produced maximum (10.184 t/ha) and the D1R1 treatment (row pure stand of Barley) produced minimum (5.036 t/ha) dry forage yield, respectively. The results of this treatment (D2R4) (1958.8 kg/ha crude protein and 26.32% crude fiber) showed the advantages of this mixture in comparison to the other treatments.

This was aimed at using saline soils in an appropriate was for cotton production by transplanting using paper pots in saline soils of Varamin. The experimental design was a Randomised Complete Blocks in the form of split-split plots with three replications. The main plots were two planting dates, May 20 and June 10. Single and double row planting were used as sub-plots and sub-sub plots were the age of transplants with four levels: direct seeding, 10, 30, and 40 days old transplants. The results showed that, delaying in the planting date reduced yield, earliness, seed weight, boll and monopodia number. Double row planting (zigzag arrangement) in comparison with single row planting, produced more; yield, stand counts, boll and monopodia number and also found out more appropriate planting arrangement in saline soils. Transplanting in comparison with direct seeding had not significant effect on yield. Among yield components, stand counts was affected by transplanting and as the age of transplants increased, the former trait was decreased. Meanwhile, transplanting increased the main root branching remarkably and shallowed them. Using of cotton transplant in delay planting conditions is a suitable practice for crop earliness.