نشریه یافته های نوین کشاورزی
سال یازدهم شماره 1 (پیاپی 41، پاییز 1395)

The aim of this research was to study the effect of planting dates of 6 Oct., 5 Nov. and 5 Dec., 2013 as S1, S2 and S3 treatments, respectively, on growth, yield and yield components of five barely cultivars (C1; Mahally as a control, C2; Abidar, C3; Valfagr, C4;Bahman and C5; Makoyei). A factorial experiment was done based on randomized complete block design with three replications at the Agricultural Research Station of Bu- Ali Sina University. Traits of plan height, number of spike m-2, number of grain spike-1, 1000- seed weight, grain yield, biological yield and harvest index (HI) were evaluted. Results showed that planting date treatment had significant effects on all traits. Maximum grain yield (420.82 g m-2) was attained at S1 treatment. S3 treatment in comparison with S1 treatment decreased grain yield up to 46.5%. At the late planting date (S3) due to exposure of plants with heat and drought of late season, grain yield of barley decreased. Also, maximum biological yield (906.33 g m-2) was achieved at planting date of 6 Oct. (S1). Between barley cultivars for traits of grain and biological yields was different significant. Valfagr cultivar with average of 382.83 g m-2, produced the highest value of grain yield and this coutivar had significant difference with other cultivars. The interaction of planting date × cultivar was significant only for grain number spike-1. Maximum and minimum values for grain number spike-1 were achieved at S1×C3 and S3×C1 treatments, respectively. In this study the most suitable planting date and barley cultivar for Hamadan region was determine planting date of 6 Oct. and Valfajr cultivar.

Today, changing the pattern of planting towards water deficit resistant  plants is proposed as a solution to drought. One of the plants resistant to drought is roselle. In this research, the effects of different levels of irrigation water, nitrogen fertilizer and potassium fertilizer on Roselle were investigated. The experiments were carried out in a split plot design with four levels of irrigation water depths (I1, I2, I3 and I4 with 25, 50, 75 and 100% of the plant water requirement respectively) and three levels of nitrogen (N1, N2 and N3 with 50, 75 and 100% nitrogen respectively) as a sub plots and three levels of potassium (K1, K2 and K3 respectively 50, 75 and 100% potassium) as subplots. At the end of the experiment, plant height, capsule weight, dry yield, anthocyanin content and irrigation water productivity were measured. The results of the experiment showed that the effects of irrigation water and potassium fertilizer were significant at 1% and 5% probability level on all measured parameters and nitrogen fertilizer on all parameters except for irrigation water productivity. The highest yield was obtained from 100% fertilizer application and 100% water requirement, but no significant effect was observed between treatment of 100 and 75% of water requirement. The highest irrigation water productivity was obtained in 75% water treatment and 100% nitrogen and potassium fertilizer application, but no significant difference was found between different treatments of nitrogen fertilizer. Therefore, considering the status of the water in the area and the reduction of water resources, the use of 75% of the water requirement will save water consumption without having a significant effect on the reduction of yield. Also, due to dry weather conditions in Sistan province, the use of potassium and nitrogen fertilizer can alleviate the drought stress damages in Roselle.

In order to evaluate the effects of foliar application of elements such as Zinc, Iron and manganese on yield and yield components of bread wheat cv. Pishgam an experiment was conducted based on a RCBD with three replications at Torbat-e-jam in 2015-2016. Factors were foliar application including Iron, Zinc, Manganese, Iron+Zinc, Iron+Manganese, Zinc+Manganese, Iron+Zinc+Manganese and control treatment. Foliar application was done using micronutrients chelates at the amount of one per thousand at stem elongation and flowering stages. The results showed that foliar application had significant effect on plant height, spike length, the number of grains per spike, and harvest index. Foliar application increased plant height significantly. The highest plant height obtained from application of Iron+Manganese, Iron+Zinc+Manganese and Zinc+Manganese. The maximum length of the spike was seen in foliar application of Iron, Zinc, Iron+Manganese which had not significant difference with control treatment. The number of grains per spike in Zinc and Zinc+Iron+Manganese treatments were higher than control. Generally, it seems that none of foliar application treatments could increase the grain yield compared to control treatment.

In order to investigate drought indices used to identify the appropriate fertilizer treatments in forage corn, hybrid Maxima (Zea mays var maxima) Separate experiments were conducted during 2014 and 2015 in Arak. The experiment was a split-split plot in a randomized complete block design with four replications. Irrigation treatments consisted of two irrigation levels (I0) and deficit irrigation (I1) as the main factor, Nytroxin in three levels: 0, 0.5 and 1 ml per 30 kg of seed and nitrogen levels of 0, 125 and 250 kg per hectare, which was considered as a minor factor. The results shown that STI, GMP and MP most appropriate indicators to determine the best fertilizer treatments is applied, to achieve the highest production yield both normal irrigation and stress. The maximum yield under both traditional irrigation and drought conditions the treatment combination of 1 ml per 30 kg seed Nitroxin with 250 kg Nitrogen per hectare (No2N2), respectively, which was selected as the most favorable treatment combination.

In order to investigate the effect of foliar application of Iron, Zinc and Boron micronutrient elements on two different irrigation regimes on soybean characteristics of M9 cultivar, a RCB design was conducted with 8 treatments in 3 replications. The experiments were done in Aleshtar, Lorestan province of Iran during two growing years between 2014 to 2016 in two separate experiments. The first irrigation was carried out after 50 mm from the pan and in the second experiment after irrigation after 100 mm from the pan. The investigated factor were micronutrient elements including micronutrient spraying, micronutrient spraying of Zinc, Iron, Boron, Zinc& Iron, Boron + Iron, Boron + Zinc and Zinc + Iron + Boron. The results showed that irrigation effect on plant height, number of nodes, number of pods per plant, 1000 seed weight, oil yield and grain yield were significant at 1% probability level. The effect of foliar application of micronutrient elements on plant height, number of nodes, number of pods per plant, number of seeds per pod, 1000 seed weight and grain yield at 1% probability level and significant number of lateral branches at 5% probability level were significant. The highest grain yield was obtained from irrigation treatments after 50 millimeters from the pan and the addition of Zinc, Iron and Boron micronutrients, with a mean of 2561 kg ha-1, and the lowest grain yield related to treatment after 100 mm of pan and lack of foliar application of micronutrient elements with an average of 1086 kg ha-1.

To evaluate the effect of tillage methods and levels of Fe and Zn as microelements on yield and yield fractions of filed corn single cross 704 cultivar, factorial experiment based on completely randomized design with three replications was performed. Experiments were carried out in 2013 in Babolsar in Mazandaran province in Iran. According to the variance analysis results tillage has statistical significant effect (P<0.01) on plant height, stem diameter, leaf length, leaf area index, forage yield and dried forage yield. Fe 30 mg/lit and 40 mg/lit Zn significantly affected the plant height, stem diameter, forage yield and dried forage yield, but did not affected leaf length and leaf area index. The results showed that tillage enhances yield and yield fractions and tillage with disk has highest effect. The highest amount of leaf area index was obtained at disk tillage with different levels of Fe and Zn.