THE SCIENTIFIC JOURNAL OF AGRICULTURE (SJA)
Year:2000 | Volume:22 | Issue:2|Papers Count:6

A 2 years experiment was conducted in 1374 and 1375 in order to investigate the effect of increasing nitrogen fertilizer and plant density on grain yield and yield components of triticale(var. juanillo - 92). The design of the experiment was a split plot in which main plots were consisted of 4 levels of N application (90, 135, 180 and 225 kg N/ha) and subplots were allocated to 3 planting densities (200, 350 and 500 plants m-2) with 4 replicates. Combined analysis indicated that grain yields were different in 2 season. Mean grain yield in first season was higher than the second. Lower grain yield in second season was due to reduction of spike number per square meter, although number of grains per spike and 1000 seed weight were higher than the first season. Results showed that higher application of N fertilizer up to 180 kg N/ha increased grain yield (5323.6 kg/ha). The higher yield (5080.6 kg/ha) obtained from 500 plants m-2 density. Interactive effect of N and plantig density on grain yield was significant. Application of 180 kg N/ha at the highest density prodused 6067.0 kg/ha of grain. This results indicated that respons of grain yield to different plant density was due to differences in N application rates. Among yield components, number of spikes m-2 and number of spikes m-2 and number of grains per spike showed that highest sensivity to both plant density and N levels. The number of spikes m-2 increased with increased in N level and planting density while the number of grains per spike decreased with increased in planting density. When planting density and N level increased 1000 seed weight decreased. Interactive effect of density and N levels on protein percentage was not significant. Highest grain protein (13.11%) was obtained from 225 kg N/ha at 500 plants m-2 density and the lowest amount protein(9.63%) obtained from application of 90 kg N/ha at 350 plants m-2 density. This results showed that the effect of N levels on grain protein was more than plant density.

Genetic parameters for birth, weaning, 6,9 and 12 month weights in a Baluchi sheep flock were studied. The genetic parameters were estimated by Restricted Maximum Likelihood method in an Animal Model. The heritability of birth weight, weaning, 6,9 and 12 month weights were 0.45(±0.02), 0.29(±0.029), 0.27(±0.03), 0.24(±0.05) and 0.33±(0.04) respectively. The Genotypic and phenotypic correlations of birth weight - weaning weight, birth weight - 6 month weight birth weight - 9 month weight, birth weight - 12 month weight, weaning weight - 6 month weight, weaning weight - 9 month weight, weaning weight - 12 month weight, 6 month weight - 9 month weight, 6 month weight - 12 month weight and 9, month weight - 12 month weight were (0.74 and 0.41), (0.71 and 0.36), (0.71 and 0.35), (0.62 and 0.31), (0.97 and 0.72), (0.93 and 0.66), (0.91 and 0.58), (0.96 and 0.79), (0.94 and 0.68) and (0.96 and 0.82) respectively.

This study was conducted to determine the apparent digestibility of tThis study was conducted to determine the apparent digestibility of the dry matter, curde protein and gross energy of soybean meal by juvenile P. indicus in Iran. A complete randomized design with four experimental diets, three replicates, and four groups of 100 shrimps (mean initial weight 7.1 ± 1.11g) per tank were employed in this study. The pellet diets (A, B, C and D) were formulated based on a refrence diet containing 1% Cr2O3 and were containing 0%, 15% 20% and 25% soybean meal and 100%, 85%, 80% and 75% refrence diet, respectively. The shrimps were kept in tanks with 1000 liters water, and the temperature, salinity, pH, dissolved oxygen, and water exchange of the tanks were 31±0.78?C, 30±1.2 ppt, 7.5-8, 5.8±0.4 ppm and 160% per day, respectively. Sea water through a sand-passed, and two cartidge filters with 25 and 50 micrometers in diameter. The shrimps were acclimated to the one of the four diets for 8-days and a 6-days period for faecal collection. The average apparent dry matter digestibility (ADMD) of A, B, C and D diets were 78.67±3.03%, 76.15±1.79%, 74.73±0.88, and 73±1.2%. The average apparent gross energy digestibility (GED) were 87.63±1.1%, 85.93±0.86%, 85.16±0.9%, and 83.87±1.7% and the average apparent organic matter digestibility (AOMD) were 82.36±2.31%, 81.65±1.94%, 80.03±0.72% and 78.5±1.56%, respectively. The differences between means were significant (P<0.05). The average apparent digestibility of crude protein (APD) of the A, B, C and D diets were 85.92±1.814%, 85.59±1.168%, 85.69±0.556%, and 85.02±0.684%, the averages of apparent lipid digestibility (ALD) were 97.41±0.78%, 96.6±0.77%, 96.27±1.37% and 95.26±0.09%. The averages of apparent digestibility of N.F.E* were 87.67±4.31%, 86.58±3.86%, 82.61±0.99% and 79.42±3.57%. The correlation between ADMD and APD was not significant but between GED and ADMD (r=0.98) and between GED and AOMD (r=0.99) was significant (P<0.01). Total digestible nutrients (TDN) of the A, B, C, and D diets were 80.74%, 80.29%, 87.74%, and 76.98%, respectively. The ADMD, APD, GED, ALD, NFE digestibility, AOMD and TDN of soybean meal were estimated to be 69.36%, 85.56%, 81.52%, 93.07%, 72.05%, 70.56% and 76.63%, respectively.

Ghorveh alluvial plain in the eastern part of Kurdistan Province, Iran, overlies a rich groundwater aquifer. Natural groundwater recharge takes place by rainfall and snowmelt infiltration on the southern slopes. Groundwater level recordings from 16 observation wells during a nine year period, 1986-1995, show that in recent years, severe drawdown of the groundwater surface has occurred. One method of solution considered is artificial recharge. The Source of water for recharge will be from surface water flows during surplus months of autumn and winter. A calibrated computer model was used for this purpose. Different recharge policies with respect to the amount, of recharge is not recommendable. It was found that the outflow volume from constant head grids depends on the amount of recharge and distance from the recharge grids.

This study was conducted to identify the effect of plant density and amount of N fertilizer on seedling transplanting of Rice cv. Red Anboori (Oriyza sativa L.). The design of the experiment was a spit plot in the randomized complete blocks with 4 replications at Research Station Shawwer of Agricultural Research Center, Khuzestan. Main plots were consisted of four plant density (15x15, 20x20, 25x25 and 30x30 cm) and subplots were four levels of N fertilizer (0, 45, 90 and 135 kg N/ha). Results of the experiment indicated that plant density did not affect grain yield but only addition of N fertilizer could increased grain yield. In this study application of 90 kg N/ha was showed the best treatment to increase the grain yield of this particular cultivar. The main yield component at the different densities was percent of grains-filled which %94.7 of variation in grain yield due to this character. Under different level of N the spikelet number and the percentage of filled grains determined by %98.47 and %1.5 of grain yield variations respectively. The correlation coefficents between grain yield and yield components confirmed multiple regression analysis. There was a negative correlation between grain yield and percentage of filled grains under different plant density. Also the results showed that there was a positive correlation of percentage grains - filled, and of spikelet number with grain yields under different N fertilizers.

Pruning level has noticeable effect on quantity and quality of the yield, vine vigor and the number of fruitfull buds. This study was conducted to determine the effect of three pruning levels (40, 64 and 88 buds left per vine) on some quantitative and qualtitative characters of the fruits and vine vigor (determined by pruning weight) of Safid-bidaneh cultivar (Vitis vinifera L.), for three successive years during 1994-96. The experimental design was a randomized complete block with three replications. In general, the effects of pruning levels on yield of vines, yield components, Brix of berries, pruning weight, percentage of bud break and fruitfull buds were statistically significant. Yield, number of cluster and percentage of fruitfull buds per vine were increased with increasing number of buds per vine, while weight of cluster, Brix, pruning weight and percentage of bud break per vine were decreased. The effect of three successive years and year Xpruning level interaction were significant on yield, number of cluster, weight of 100 berries, pruning weight and percentage of fruitfull buds which decreased on vines with 88 buds. But had no significant effect on cluster weight, Brix and percentage of bud break. During three successive years, the yield and vine vigor were not decreased on vines with 40 or 64 buds left per vine. According to the obtained results, vines left with 64 buds could be recommend in practice.