Effect of Spacing and Growth Retardants on Guava (Psidium guajava L.) Plant Vigour

Four year old plants of guava cv. ‘Sardar’ growing at different spacing viz. 6x2 m, 6x3 m, 6x4 m and 6x5 m were sprayed with paclobutrazol (PBZ) and ethephon @ 500 ppm, 1000 ppm each in the month of March. Observations revealed that plant spacing and growth regulator treatments significantly influenced the vegetative growth of trees. Stock and scion girth increased with ethephon treated plants. Although, plant growth in terms of height, spread and overall tree canopy restricted under all treatments, effect of PBZ was more pronounced. More than 30% reduction in mean tree canopy was recorded in PBZ 1000 ppm treated plants. The plants at 6×4 m spacing exhibited maximum (more than 50%) restriction in plant growth as compared to untreated plants. Vegetative growth of trees increased with increase in plant spacing except tree height and tree spread (E-W) which was recorded higher with decreased plant spacing. However, fruit yield per unit area was improved with PBZ treatments during both seasons. Higher yield was recorded in plants at closer spacing in rainy season but in winter season plants exhibited inconsistence yield behaviour with respect to plant spacing.