نشریه یافته های تحقیقاتی در گیاهان زراعی و باغی
سال دهم شماره 1 (بهار و تابستان 1400)

In order to investigate the effect of Paraquat herbicide on induced drying of plants and therefore, early harvest of crimson clover seeds in Alborz 1 cultivar a factorial experiment was conducted using a randomized complete block design with three replications, and 12 treatments for two cropping seasons 2012-2013 and 2013-2014. The first factor was different dosage of Paraquat consisted of four levels (a1= no herbicide, a2= 50% less than recommended dose (2 litreha-1), a3= recommended dose (4 literha-1) and a4= 50% more than recommended dose (6 litreha-1) and the second factor was phonological stage of the plants when Paraquat herbicide was applied consisted of three levels. (b1= Physiological maturation of seed, b2= 50% browning of the inflorescence, b3= complete inflorescence browning). Results showed that different amount of Paraquat in all three phenological stages had significant effects on seed yield, number of seeds per in florescence and 1000-seed weight compared to the control treatment with no use of herbicide. Result of the two-years study showed that a3b2 treatment with seed yield of 585.83 kgha-1 had the highest seed yield. However, there was no significant difference between application of 2 and 4 liters of Paraquat (Gramoxone herbicide) per hectare at the browning stage of 50% of inflorescences. Therefore, a2b2 treatment with seed yield of 585 kgha-1 and near 25% increase compared to the control is recommended for seed production of crimson clover Alborz 1 cultivar in Karaj region.

In order to increase time interval of the fruit supply and to produce variability and benefit from the marketable characteristics of superior apricot germplasm, six promising genotypes selected among native genotypes of East Azerbaijan province, Iran were evaluated from 2004 to 2018. In these studies, the generative and vegetative characteristics of these genotypes were assessed during the implementation of seven research projects and studied genotype were compared with the cv. Ordubad 90 (as control). The results showed that fruit of genotype No. 190 was ripened at least 20 days later than control. Although the mean differences of fruit volume and weight of this genotype were non-significant with control but its flesh firmness in the physiological ripening stage was significantly more than the control (3 kgcm-2). Also, a significant difference was observed between the weight ratio of fruit/stone of genotype 190 and control having ratios of 25.6 and 16.6, respectively. The fruit of this genotype with 25% moisture reduction was dried ideally and its organoleptic characteristics remained stable for at least one year in cold storage conditions. Studies also revealed that the superiority of the characteristics of yield efficiency, relative coloring of fruit, ripening date, storage period, shelf life and transportability of genotype No. 190 in comparison with control and therefor this genotype was released and introduced as "Sahand 97" commercial name to the Iran's horticultural community.

In order to evaluate the effect of row spacing and seed rate on yield and yield components of safflower cultivars, a field experiment was conducted in research field of Seed and Plant Improvement Institute, Karaj, in 2015-2016 and 2016-2017 cropping seasons. A factorial experiment based on a randomized complete block design with three replications was conducted in the field experiments. Factors of the experiment consisted of two row intervals of 30 and 60 cm, two plant distances of 40 and 60 plants per square meter, and three safflower cultivars namely Padideh, Golmehr and Goldasht. In this study, the simple effect of row spacing on yield and yield components, simple effect of density on yield, oil yield, and number of grain per boll, and the interaction effect of row spacing × plant density on number of grains per boll were significant. Also, three safflower cultivars had significant differences for plant height, grain yield and oil yield. The results of this study showed that the highest grain yield was obtained at 30 cm row spacing (2312 kgha-1) and density of 60 plants per square meter (2263 kgha-1). Also, Goldasht and Golmehr had the higher grain yield compared to Padideh. Thus, the best recommendation for planting pattern of safflower cultivars in moderately cold areas is row spacing of 30 cm (two rows on stack) and density of 60 plants per square meter.

Anousha cultivar is results of a cross-pollination of Agria and promising colon 397009, and various field and laboratory experiments during 12 years in the Seed and Plant Improvement Institute Karaj, Iran. To release Anousha variety, single plant selection, visual assessment, preliminary and advanced yield trials, adaptability test, study on resistance to fungi, bacteria and viruses was carried out in different places such as Karaj, Ardabil, Hamadan, Esfahan and Mashhad (Jolgehrokh). Although, Anousha cultivar had superiority to the Agria in terms of yield, but scatter Bi-plot analysis with respect to average yield and relative coefficient of excellence showed that its relative coefficient of excellence was almost the same as that of the Agria. The yield of Anousha cultivar in an on-farm study in Hamadan and Ardabil areas was 12.9% and 12.4% higher than that of Agria (check cultivar), respectively. Anousha cultivar is highly resistant to PVY and PVX that are very important and harmful viruses around the world. The reaction of Anousha to Alternaria alternata, Rhizoctonia solani (race AG-3), Rhizoctonia solani (race AG-4) and Rhizoctonia solani (potato black scurf) is semi sensitive, semi tolerant, tolerant and semi tolerant, respectively. The tuber dry matter of Anousha is 2% more than Agria and is excellent for frying and processing purposes. Anousha as a new potato cultivar is suitable for spring cultivation in the cold and moderately cold regions of Iran.

This study was carried out to determine the profitability indices of irrigated wheat cultivar Pishtaz in Tehran province during the period of 2006-2015. Methodology of this research was based on economic surplus approach. Based on the results, the estimated net present value of the economic surplus for Pishtaz cultivar in the target region was 7.72 Iranian billion rials. The estimated benefit to cost ratio of planted Pishtaz cultivar was 1.2 and its internal rate of return was estimated to be more than the discount rate. Thus, based on the estimated benefit to cost ratio of this cultivar in the target region which was more than one and its estimated internal rate of return which is more than long term discount rate of the banking system, breeding programs for this cultivar and its cultivation is identified to be economic in the target region. Also, it is recommended that due to the important role of the extension service in promotion and development of the cultivation of improved wheat cultivars, agricultural extension agents should promote the profitable wheat cultivars for the target area and persuade farmers to cultivate such varieties to get a higher income.

The High-yielding cultivars must show their superiority in terms of seed yield and agronomic traits and should have yield stability across wide range of environmental conditions as well as under farmer’s conditions. Therefore, in the process of releasing a new cultivar usually after evaluation of candidate lines in the research stations, these lines must be also tested in the on-farm trials under conditions similar to those of farmers conditions. In the present study, the promising line HW118 was compared with the local check (Okapi) in an on-farm trials in two regions of the Kermanshah province (Harsin and Allahiar Khani). The results showed that in both regions grain yield of line the HW118 was higher than local check Okapi at delayed planting date. In Harsin, grain yield of line HW118 was 3226 kgha-1 where local check Okapi had only 2850 kgha-1 grain yield. Similarly, in Allahiar Khani line HW118 had grain yield of 4125 kgha-1 that was 25% higher than that of local check Okapi with grain yield of 3300 kgha-1.

A bread wheat breeding line that led to release of Tallaei cultivar introduced from International Research Center for Maize and Wheat (CIMMYT) to Iran through an international nursery in 2009 and was evaluated in a primary trial in Islam Abad-Gharb research station and due to its favorable characteristics was selected for further evaluation. This line showed grain yield of 6967 and 5370 kgha-1 under normal irrigation and terminal drought conditions, respectively, while mean grain yields of four check cultivars: Parsi, Sivand, Bahar and Pishtaz for those two conditions were 6857 and 3850 kgha-1, respectively, Aforementioned line showed grain yield of 4851 kgha-1 in advanced yield trial of temperate regions breeding program under water deficit conditions compared to 4631 khha-1 of drought tolerant check cultivar "Sirvan" in three locations, hence selected for final evaluation in adaptation trial. Grain yield of this line which was presented as M-91-18 at the adaptation trial was 7563 and 6385 kgha-1 against 8022 and 6200 kgha-1 of Parsi check cultivar under normal and water stress conditions, respectively, during two cropping seasons 2012-13 and 2013-14. This line showed overall mean grain yield, of 9583 and 8042 kgha-1 in normal irrigation and water deficit conditions under extensional farmer fields, respectively. For these two conditions check cultivar Parsi showed 7875 and 6828 kgha-1 records. Grain yield potential of this line was recorded as 10070 and 10670 kgha-1 in Alborz and Kermanshah farmers' fields, respectively. According to the latest evaluations the response of this line to yellow and leaf rusts was moderately resistant under severe artificial infection. Wheat line M-91-18 has considerable earliness and good bread making quality and based on its good agronomic characteristics in 2017 this line was released as Tallaei, for cultivation under normal and terminal moisture stress conditions in temperate agro-climatic regions.