TY - BOOK AU - Eldhhose Abraham AU - Jacob John (Guide) TI - Allelopathic effect of trees grown in homesteads of Kerala on ginger (Zingber officinale Roscoe) U1 - 630 PY - 2016/// CY - Vellayani PB - Department of Agronomy, College of Agriculture KW - Department of Agronomy N1 - MSc N2 - The research project entitled “Allelopathic effect of trees grown in homesteads of Kerala on ginger (Zingiber officinale Roscoe)” was conducted during the period from February to December 2015. The objective was to investigate the allelopathic effect of trees commonly planted in the homesteads of southern Kerala on sprouting, growth and yield of ginger. The study involved two laboratory bioassays and two pot culture experiments, all laid out in completely randomized design. The first bioassay comprised eight tree leaf leachates each at two concentrations and one control totaling 17 treatments each replicated thrice [jack, mango, tamarind, matty, wild jack, teak, rubber, panal each at 1:10 and 1:15 concentration, and one absolute control (distilled water)]. The second bioassay was carried out in the same manner with leaf extract. The two pot culture experiments were laid out in completely randomized design. The first pot culture experiment was laid out with 17 leaf leachate as treatments, each replicated thrice. The second pot culture experiment, was carried out to study the effect of different tree leaf mulches and comprised nine treatments with three replications - M 1 (mulching with fresh leaf loppings of jack), M 2 (mango), M 3 (tamarind), M 4 (matty), M 5 (wild jack), M 6 (teak), M 7 (rubber), M 8 (panal), M 9 (control with newspaper). Mulch was applied as per the KAU recommendations. The ginger variety, ‘Karthika’, was used for the study. The first bioassay revealed that the leaf leachates of tamarind (T 3 ) and mango (T 2 ) severely inhibited the sprouting and the shoot growth of ginger rhizome. All the leaf leachates reduced the root growth and number of roots significantly and tamarind (T 3 ) resulted in the highest inhibition. The inhibitory effect was alleviated with dilution. In the second bioassay, leaf extracts of tamarind (T 3 ) significantly inhibited sprouting of ginger. Leaf extracts of mango and tamarind recorded significantly lowershoot growth. Leaf extracts of mango (T 2 ), tamarind (T 3 ) and teak (T 6 ) inhibited the root growth and number of roots significantly. Leaf extracts of panal (T 8 ) had a significant stimulatory effect. In the first pot culture study, plants treated with leaf leachate of tamarind (T 3 ) had least height and number of tillers at 2 months after planting (MAP), while applying panal (T 8 ) leaf leachate resulted in maximum plant height at 4 and 6 MAP. The number of leaves was highest in applying panal (T 8 ) leaf leachate, at 6 MAP. Tamarind (T 3 ) leaf leachate significantly inhibited the root volume and root weight. Among the physiological parameters, stomatal conductance alone was affected by the leaf leachate of trees. Application of tamarind (T 3 ) leaf leachate resulted in lesser yield (443.56 g plant -1 ). However, application of panal (T 8 ), rubber (T 7 ) and matty (T 4 ) leaf leachates produced significantly higher rhizome yield per plant. In the second pot culture experiment involving mulching with the tree leaf loppings, plant height was significantly less in treatments M 2 (mango) and M 3 (tamarind). Rhizome yield was significantly higher when mulched with panal (653.50 g plant -1 ) and was on a par with newspaper (637 g plant -1 ) and rubber (621.40 g plant - 1 ) leaves. However, mulching with mango leaves resulted in significantly lesser yield (512.09 g plant -1 ). Another interesting observation was that in the control where newspaper were used as mulch, the yield was high (637 g plant -1 ) and comparable to mulching with panal, rubber, teak, matty, wild jack and jack leaves. Hence ginger is grown in homesteads and terrace gardens, if available newspaper can be used for mulching. Based on the results of the experiments, it can be concluded that leaf leachates and extracts of tamarind, mango and teak are inhibitory to sprouting and growth of ginger. Hence, when ginger is planted under the canopy of these trees care should be taken to alleviate the inhibitory effect. Leaf lopping of tamarind is not ideal formulching in ginger. Leaf loppings of panal, rubber or matty can be recommended for mulching in ginger UR - http://krishikosh.egranth.ac.in/handle/1/5810137938 ER -