كليدواژه :
دفعات آبياري و رژيم آبياري , سرعت رشد محصول , شاخص سطح سبز , شاخص‌هاي رشدي توده بومي زيره‌سبز
چكيده فارسي :
زيره سبز (Cuminum cyminum L.) يكي از مهمترين و اقتصادي ترين گياهان دارويي است كه مي تواند در مناطق خشك و نيمه خشك ايران براي توليد در شرايط كمبود آب حائز اهميت فراوان باشد. جهت بررسي شاخص هاي رشدي توده بومي زيره‌سبز و يك رقم هندي (Cuminum cyminum L.) در شرايط تنش خشكي و شوري آزمايشي به صورت كرت هاي دوبار خرد شده در قالب طرح بلوك هاي كامل تصادفي با سه تكرار در مزرعه تحقيقاتي دانشگاه فردوسي مشهد در سال زراعي 88-1387 انجام شد. كرت‌هاي اصلي در چهار سطح شامل تعداد آبياري (يك تا چهار نوبت) در طول فصل رشد زيره‌سبز و كرت‌هاي فرعي در دو سطح شامل آبياري با آب با هدايت الكتريكي يك دسي زيمنس بر متر (شاهد) و آب شور با هدايت الكتريكي پنج دسي زيمنس بر متر و كرت هاي فرعي فرعي در دو سطح شامل توده بومي سرايان و رقم هندي بودند. نتايج نشان داد كه تجمع وزن خشك، شاخص سطح سبز، دوام شاخص سطح سبز و سرعت رشد محصول تحت تأثير اثرات منفي تنش قرار گرفتند. همچنين دو و سه نوبت آبياري بيشترين اثر مثبت را از نظر اين شاخص ها داشتند و پايين ترين ميزان از يك و چهار نوبت آبياري با آب شور به دست آمد. در بين رقم و توده مورد مطالعه نيز توده سرايان در تمامي شاخص هاي مورد بررسي نسبت به رقم هندي برتري داشت. تيمار استفاده از آب شيرين نيز نسبت به تيمار آب شور از نظر اين شاخص ها برتري داشت. بنابراين، با توجه به نتايج به دست آمده تيمار استفاده از آب شيرين به همراه دو يا سه بار آبياري براي حصول عملكرد بالا توصيه مي‌شود.
چكيده لاتين :
Water shortage in Iran has always been a limiting factor for crop cultivation. Drought stress at different
growth stages, especially flowering and grain filling stages decreases the yield of the plants. Drought stress may
limit yield of medicinal and aromatic plants by reducing the harvest index (HI). This can occur even in the
absence of a strong reduction in total medicinal and aromatic plants dry matter accumulation, if a brief period of
stress coincides with the critical developmental stage around flowering stage. Water stress is the most influential
factor affecting crop yield particularly in irrigated agriculture in arid and semi-arid regions. It is necessary to get
maximum yield in agriculture by using the least available water in order to get maximum profit per unit area
because existing agricultural land and irrigation water are rapidly diminishing due to rapid industrialization and
urban development. In general, 15% of the Iran lands are saline and sodic (Parsa, 2000) and it dues to the use of
widespread of water resources and the soil salinity of the farms. Unfortunately this factor (soil salinity) gradually
becomes more serious, in fact even in none-saline water irrigation with salt accumulation in the soil in long
period of time it may increase and the result will be the limitation of the products (Sharma, 1996). The analyzing
of the growth and product is a method for discovering the factors which are effecting on the plants. The purpose
of the analyzing of the plants growth is the reaction of the plants to the environmental factors (Sangwan et al.,
1994). Cumin (Cuminum cyminum) is one of the most important economic and medicinal plants that can growth
in arid and semi-arid conditions. Cumin is mostly grown in China, Uzbekistan, Tajikistan, Iran, Turkey,
Morocco, Egypt, Syria, Mexico, Chile and India. In the ancient Egyptian civilization cumin was used as spice
and as preservative in mummification. The purpose of this study was the effect of drought and salinity in
different phenological stages on some of the growth characteristics of cumin cultivars.
Material and method
The experiment was split plot in a randomized complete block design with three replications, in Ferdowsi
University of Mashhad, Iran during growing season of 2008-2009. Factors were including irrigation times (I1:
one times irrigation, I2: two times irrigation I3: three times irrigation and I4: four times irrigation (control) and
with two levels of salinity stress (irrigation with normal water and saline water five dS.m-1) and two cumin
cultivars (Sarayan, Indian cultivar RZ 19). To determine the physiological properties of cumin every 14 days
five plants from the bottom half of each plot was randomly picked and transferred to the laboratory and some
specifications such as green area, plant dry weight and the number of side branches was measured. For Data
analysis software Mstat-C was used. The growth parameters were calculated and graphs were drawn by Excel
software.
Results and discussion
Dry weight variations were significant by increasing irrigation. The highest amount of dry weight for
treatment with three times irrigation (260 g.m-2) and the lowest amount for one time irrigation (193.5 g.m-2) were
recorded. Salinity too causes decline dry weight in such treatments that dry weight with the use of normal water
was 252 g.m-2 and with saline water was 199.6 gr/m-2. In the various experiments conducted on cumin, it was
found that the process of creating green area in this plant is slow, especially in the early period. According to
various sources, maximum green area index for cumin not exceed the greater of 1.5 and for a large part of
growing season is less than one. One time irrigation treatment showed the lowest green area index. The highest CGR was in three times irrigation with 7.92 g.m-2.day-1 and the lowest CGR was in one time irrigation with 4.87
gr.m-2.day. Leaf area index duration increased with more irrigation. Green area index duration was 15.63 m2 leaf.
m-2 land in three times irrigation and By reducing irrigation frequency has been significantly reduced.
Conclusion
In this experiment, all of the growth indices were affected by drought and salinity. The lowest specifications
were in one and four irrigation times with saline water.
