Uludag Ahmet, Gozcu Dogan, Rusen Mine, Guvercin Ramazan Sadet, Demir Abdullah
Izmir Agricultural Quarantine Directorate, Liman Caddesi, No. 25, Alsancak, Izmir, 35240, Turkey.
Pak J Biol Sci. 2007 Feb 1;10(3):523-5. doi: 10.3923/pjbs.2007.523.525.
Cotton is an important crop in Turkey. Johnsongrass is one of the worst weeds in cotton fields worldwide. Field experiments were carried out in 1992, 1997 and 2002 to show the effect of johnsongrass densities on cotton yield. Johnsongrass densities were 0, 1, 2, 4, 8, 16 and 32 plants per 8 m and 0, 3, 6, 8, 11, 14 and 22 plants per 4 m of cotton row. Data were fitted to equations Y = 1/(a+bX8) in 1997 and 2002 for the number of johnsongrass in 8 m of row length and Y = 1/(a+bX4(-1/2)) in 1992 and 1997 for the number of johnsongrass in 4 m of row length. Cotton yield was affected by all johnsongrass densities. One johnsongrass plant in 8 m of cotton row decreased cotton yield 4.82 and 9.42% in 1997 and 2002, respectively.
棉花是土耳其的一种重要作物。约翰逊草是全球棉田最有害的杂草之一。1992年、1997年和2002年开展了田间试验，以展示约翰逊草密度对棉花产量的影响。约翰逊草密度为每8米棉行0、1、2、4、8、16和32株，以及每4米棉行0、3、6、8、11、14和22株。1997年和2002年，针对8米行长的约翰逊草数量，数据拟合方程Y = 1/(a + bX8)；1992年和1997年，针对4米行长的约翰逊草数量，数据拟合方程Y = 1/(a + bX4(-1/2))。所有约翰逊草密度均对棉花产量产生影响。1997年和2002年，每8米棉行有一株约翰逊草，棉花产量分别降低4.82%和9.42%。
