|Author:||Benam, M. B. K. ; Hassanpanah, D.|
|Book Group Author:||NA|
Water deficit is an important stress factor in potato cultivation and leads to yield decrease. To evaluate 20 potato cultivars with respect to water deficit and select suitable cultivars to arid and semi-arid zones, an experiment was conducted in 2000-01 in Iran. The effects of 6, 12 and 18 days irrigation periods and three drought stages (from planting to emergence of seedlings, from emergence of seedlings to tuber setting and from tuber setting till maturation) on emergence time, tuber setting and maturation date were determined. In the growth period, the main and lateral stem number, diameter, plant height, tuber number, and tuber weight were measured. Combined ANOVA showed that there were significant differences in the irrigation treatments in tuber yield, number, weight and number (35-55 mm), as well as tuber bigger than 55 mm. There were significant differences in tuber yield, weight and number (<35 and 35-55 mm) among the cultivars. Mean comparison of 2 years of irrigation periods showed that water stress led to decreases in tuber yield, weight and number (>55 mm). In comparison, the control irrigation led to an increase of 4.25 t in tuber yield per ha with respect to mild condition and 12.18 t in tuber yield per ha with respect to severe conditions. Severe stress decreased tuber weight by 174.7 g and tuber yield (>55 mm) number by 0.79. Water stress at planting time increased the tuber yield, number, weight, number (35-55 mm), number (>55 mm) and decreased the tuber number (<35 mm) more than the tuber setting time. The tuber-setting stage was the most sensitive stage and led to the highest decrease in yield. Vital, Mondial, Caesar, Draga, Cosmos, Cosima, Ilona and Granola showed the highest yields of 28.51, 27.83, 26.42, 26.01, 25.58, 24.81, 24.53 and 24.42 t/ha, respectively. These cultivars also had the highest tuber number and weight. Cosima, Vital, Serenade, Draga, Sinja and Idul produced the highest tuber number (35-55 mm). The correlation between tuber yield and number, weight, number (>55 mm) and leaf area was significantly positive and with plant height and main stem number was negative and non-significant. Modified stress tolerance index showed that Caesar, Vital, Ilona, Mondial and Draga had high tolerance to stresses in irrigation periods, and Mondial, Draga, Vital, Cosmos and Cosima had high tolerance to water stress. These cultivars showed high yield under stressed and non-stressed conditions. Cluster analysis showed 4 groups.
|Pages:||183 - 188|
cluster analysis, correlation analysis, crop growth stage,crop yield, cultivars, drought, drought resistance, emergence,irrigation, maturation period, potatoes, stems, tubers, water deficit,water stress, yield components, yield correlations, Iran, Solanumtuberosum, West Asia, Asia, Middle East, Developing Countries, ThresholdCountries, Solanum, Solanaceae, Solanales, dicotyledons, angiosperms,Spermatophyta, plants, eukaryotes, cultivated varieties, droughttolerance, watering, Field Crops (FF005) (New March 2000), PlantBreeding and Genetics (FF020), Plant Production (FF100), EnvironmentalTolerance of Plants (FF900), Soil Water Management (Irrigation andDrainage) (JJ800) (Revised June 2002) [formerly Soil Water Management]