Analysis of growth response of cool season cereals and #8220;wheat vs. rye and #8221; grown in organic and inorganic soils

Abstract

Plant growth response of wheat (Triticum aestivum L.) vs. rye (Secale cereale L.) to organic and inorganic soils was performed at 30, 60 and 90 days after emergence (DAE). A pot experiment was conducted at The Dryland Agriculture Institute, West Texas A&M University Texas, USA, during winter 2009-2010 using three organic soil mixtures (potting soil/compost) [Miracle Grow (MG), Sunshine Peat Moss (SPM), and Garden Basic Peat Humus (GBPM)], and two inorganic soils [Canyon Soil (CS) and Amarillo Soil (AS)]. The following measurements were performed to quantify plant growth: leaf area plant-1 (LAPP), leaf area expansion rate (LER), specific leaf area (SLA) , leaf area ratio (LAR), plant height, stem elongation rate (SER) , root length (RL), number of roots plant-1 (NRPP) number of tillers plant-1 (NTPP), stem girth, carbon exchange rate (CER), absolute growth rate (AGR), crop growth rate (CGR), and net assimilation rate (NAR) The experiment was performed in completely randomized design with three replicates. The objective of this experiment was to check whether growth response of wheat vs. rye differ under organic and inorganic soils? The results revealed that both crops responded differently in terms of growth at different crop growth stages under organic and inorganic soils. The planned mean comparison indicated that both wheat and rye grown under organic soils had higher LAPP, LER, SLA, LAR, plant height, SER, root length, NRPP, NTPP, AGR and CGR than crops grown under inorganic soils. Interestingly, the stem girth, CER and NAR declined under organic soils as compared with inorganic soils. The leaf characteristics (LAPP, LER, SLA and LAR) was greater under GBPM > MG > SPM > AS > CS, and rye performed better than wheat at different growth stages. Plant height, SER and root lengths was higher under MG > GBPM > SPM > AS > CS, however no significant differences were found between the two crops at different growth stages. The NRPP and NTPP were more under MG > GBPM > SPM > AS > CS, and rye performed better than wheat. The AGR and CGR values were more under MG > GBPM > SPM > AS > CS, rye performance was good at 60 DAE, and wheat ranked first at 30 and 90 DAE. Both AGR and CGR values were higher at 90 > 60 > 30 DAE indicated increase with the passage of time. The AGR and CGR showed positive relationship with increase in LAPP, LER, plant height, root length, NRPP and NTPP. The shoot to root ratio decreased with the passage of time and showed negative relationship with increase in root length.