پديد آورندگان :
ملاحسيني، حميد سازمان تحقيقات، آموزش و ترويج كشاورزي، اصفهان - مركز تحقيقات و آموزش كشاورزي و منابع طبيعي - بخش تحقيقات خاك و آب , جلالي، اميرهوشنگ سازمان تحقيقات، آموزش و ترويج كشاورزي، اصفهان - مركز تحقيقات و آموزش كشاورزي و منابع طبيعي - بخش تحقيقات علوم زراعي- باغي
كليدواژه :
كارآيي مصرف آب , عملكرد , سولفات پتاسيم , اكسيد پتاسيم
چكيده فارسي :
به منظور بررسي تاثير محلول پاشي پتاسيم و دفعات آن، در كاهش اثرات شوري آب آبياري (6/1 دسي زيمنس برمتر)، آزمايشي در سال 1392 در مركز تحقيقات كشاورزي اصفهان با استفاده از آزمايش فاكتوريل در قالب طرح بلوك كامل تصادفي در چهار تكرار انجام شد. تيمارهاي محلول پاشي شامل تيمار شاهد، سولفات پتاسيم (K2SO4(10ppm و اكسيد پتاسيم(K2O (2/5 ppm و دفعات محلول پاشي شامل سه مرحله ي كامل شدن رشد رويشي (شروع گل دهي)، مرحله رشد سريع غده ها (ظهور كامل گل ها) و مرحله حجيم شدن غده ها (دو هفته پس از مرحله ظهور كامل گل ها) بود. برهمكنش محلول پاشي پتاسيم و دفعات محلول پاشي، به جز بر صفات تعداد غده در بوته و درصد ماده خشك غده، بر ساير صفات مرتبط با عملكرد و همچنين كارآيي مصرف آب تاثير معني دار داشت. تيمار سولفات پتاسيم با سه نوبت محلول پاشي و تيمارهاي اكسيد پتاسيم با دو و سه نوبت محلول پاشي، به ترتيب با عملكردهاي قابل فروش 45450، 42700 و 47150 كيلوگرم غده در هكتار نسبت به ساير تيمارها برتري معني دار داشتند. ميانگين وزن غده در تيمارهاي سه نوبت محلول پاشي سولفات پتاسيم، و دو و سه نوبت محلول پاشي اكسيد پتاسيم، نسبت به تيمار شاهد به ترتيب 19، 17 و 21 درصد افزايش وزن داشت. سه نوبت محلول پاشي سولفات پتاسيم و سه نوبت محلول پاشي اكسيد پتاسيم با كارآيي مصرف آب 4/5 كيلوگرم بر متر مكعب نسبت به تيمار شاهد 27 درصد افزايش داشت. نتايج اين پژوهش نشان داد محلول پاشي پتاسيم مي تواند به عنوان يك راهكار عملي براي كاهش اثرات شوري در گياهي با نياز پتاسيم بالا مانند سيب زميني مطرح باشد.
چكيده لاتين :
1Introduction The potato of commerce (Solanum tuberosum L.) is an annual dicot species. It is an autotetraploid with 4x=48 chromosomes. In Iran the consumption per capita of potato is over the 35 kg. Potato production is usually done without reducing yield in the irrigation water salinity 1-2 dS m-1, but 4.2 dS m-1 salinity reduces yield by 26 percent. 10, 25 and 50 percent yield reduction have been reported in soil electrical conductivity 2.5, 3.8 and 5.9 dS m-1, respectively . Between the ability of plant species to maintain potassium levels and their tolerance to salinity is positive correlation and on this basis nutritional irregularity due to increased salinity can be compensated by increasing of potassium fertilizer. In tolerant plant species, during times of increased salinity, selective absorption of potassium increased. The ability of plants to maintain a certain level of K/Na within the cell is essential for salt tolerance and sometimes of these ratios is used as indicators of salinity tolerance. Potato yield in response to salt stress, according to a variety of uses, can be reduced from 20 to 85 percent. Harmful effects of salinity in the beginning stages of tubers and tuber growth stage are important, therefore, tuber number and tuber size are two important components of yield which may reduce in the effect of salinity. Accelerate the aging process of the shoot, unwanted earliness, are of the reasons for the reduction in tuber size. Materials and Methods A field experiment was conducted in the agricultural and natural resources research center (31° 32´ N, 51° 51´ E), Isfahan, Islamic Republic of Iran. According to twenty years statistics, rainfall and temperature means for experiment location were 110 mm and 25 °C, respectively. The experiment was conducted as a factorial in a completely randomized block design with four replications. The treatments were three levels of foliar K application (control, K sulphate 10 ppm, and 2.5 ppm of potassium oxide), and the number of times foliar spray were included index values than the other treatments. The negative effect of irrigation with saline water on assimilate partitioning to the tuber is cause of the reduction of harvest index. Water use efficiency with foliar application of three times potassium sulfate or potassium oxide was 27% higher than the control treatment (4.5 kg m-3). The use of sufficient potassium in such a situation is not only necessary to maintain osmotic potency, the continuation of assimilates in phloem, and loading these vessels but also plays an important role in detoxification of sodium ions. In salinity stress, accelerated aging and earliness shoot unintentionally, are the reasons for the reduction in tuber size. Conclusions The results showed that foliar application of potassium, especially in two or three times (depending on the type of fertilizer application) can result in harmful effects of salinity and leads to an increase in tuber yield. In relation to foliar K application, some cases are necessary: First, due to the sensitivity of potato to fungal diseases, foliar application of fungicides and K fertilizers can be simultaneously tested in salt stress conditions. Second, the salinity considered for this study was 6.1 dS m-1. This amount of salinity to the potatoes is too much so it may be recommendable to spray less frequently at lower salinity levels.
