Allometry and yield components of maize (Zea mays L.) hybrids to various potassium levels under saline conditions

Abstract

A field experiment was conducted to study the response of two maize hybrids to external K application under saline field conditions (ECe 5.71-8.91 dS m-1). The data showed that there was an increase in the different growth and yield components with the increase in the external K. The increase was more pronounced when K was applied at the rate of 175 kg ha-1 with respect to control treatment. The enhanced growth and yield of these hybrids under saline conditions might be due to the response of K application, resulting in reduced Na uptake. The results indicated that the hybrids Pioneer 32B33 perform better than Dekalb 979 and economical yield can be obtained when potassium was applied at the rate of 125 kg ha-1.

Salt stress in maize: effects, resistance mechanisms, and management. A review

“…The high values for sodium/potassium, sodium/calcium, and sodium/magnesium ratios in the total plant and apoplast and symplast of expanding tissues in maize confirm that impaired transport of potassium, calcium, and magnesium by sodium might upset plant metabolism leading to reduced growth under saline conditions (Shahzad et al 2012). In another study, a substantial rise in sodium contents in ten maize hybrids with increasing salinity levels decreased calcium and potassium contents leading to reduced potassium/sodium and calcium/sodium ratios (Akram et al 2010a).…”

“…At higher levels of salt stress in a solution culture study, the two tolerant maize hybrids (Pioneer 32B33 and Pioneer 30Y87) of ten hybrids under study maintained the highest potassium and calcium contents resulting in superior potassium/sodium and calcium/sodium ratios and produced more biomass (Akram et al 2010a). Moreover, salt-tolerant hybrids maintained higher levels of potassium in shoots than sodium while salt-sensitive hybrids accumulated more sodium in shoots, and differential selectivity of plasma membrane may be associated with the sensitivity/resistance of these hybrids (Akram et al 2010a).…”

“…At higher levels of salt stress in a solution culture study, the two tolerant maize hybrids (Pioneer 32B33 and Pioneer 30Y87) of ten hybrids under study maintained the highest potassium and calcium contents resulting in superior potassium/sodium and calcium/sodium ratios and produced more biomass (Akram et al 2010a). Moreover, salt-tolerant hybrids maintained higher levels of potassium in shoots than sodium while salt-sensitive hybrids accumulated more sodium in shoots, and differential selectivity of plasma membrane may be associated with the sensitivity/resistance of these hybrids (Akram et al 2010a). According to Mansour et al (2005), salt stress substantially increased sodium accretion at the expense of potassium and calcium in the salt-resistant maize cultivar (Giza 2) than the salt-sensitive cultivar (Trihybrid 321), while Cramer et al (1994) reported twice as much sodium accretion in the highbiomass-producing hybrid (Pioneer 3578) than the lowbiomass-producing hybrid (Pioneer 3572) suggesting that maize growth was primarily affected by osmotic factors under salinity.…”

“…Salinity reduces shoot growth by suppressing leaf initiation and expansion, as well as internode growth, and by accelerating leaf abscission (Rios-Gonzalez et al 2002;Akram et al 2010a;Qu et al 2012). Salt stress rapidly reduces leaf growth rate (Munns 1993) due to a reduction in the number of elongating cells and/or the rate of cell elongation (Szalai and Janda 2009).…”

Foliar Applied Potassium and Zinc Enhances Growth and Yield Performance of Maize under Rainfed Conditions

“…Days to 50% silking were minimum when potassium applied at foliage stage (Abid et al, 2016). Akram et al (2010) reported that zinc application both at soil and foliage led to Particulars T1 T2 T3 T4 T5 T6 T7 T8 T9 Urea 9672 9672 9672 9672 9672 9672 9672 9672 9672 DAP 17750 17750 17750 17750 17750 17750 17750 17750 17750 SOP 13200 13200 13200 SSFK 568 568 568 Zinc Sulfate 3000 3000 3000 SSFZn 160 160 160 Common cost 26330 26330 26330 26330 26330 26330 26330 26330 26330 Total cost 53752 56752 53912 66952 69952 67112 54320 57320 …”