RÉSUMÉ
Cashewnut (Anacardium occidentale L.) is an export-oriented plantation crop. The VRI-3 cashew plantation, utilizing a 7 x 7 m low-density (LD) system with approximately 200 plants ha-1, falls short of meeting the country's import and export demands. Consequently, a high-density planting (HDP) system was developed in Tamil Nadu to enhance India's cashew production. Further advancement through ultra-high-density planting (U-HDP) has proven effective, achieving a plant population of about 1250–1600 plants per hectare. In addition to the increased number of plants in the U-HDP approach, morphological characteristics such as tree height, trunk height, trunk girth, and canopy ground coverage were studied. The impact of these morphological changes resulting from an increased tree population on physiological parameters like Leaf Area Index (LAI) and light extinction coefficient (k) was also analysed. This analysis was carried out using the ‘Ceptometer’ model AccuPAR LP-80 device, aiming to determine how these changes might interfere with productivity and subsequently influence the cashew plantation's production capacity.
RÉSUMÉ
Study was undergone to evaluate the efficacy of floatation grading on the seeds of Amaranthus Cv. PLR 1 using organic solvents in Department of Seed Science and Technology, TNAU, Coimbatore during March 2023.The experiment was laid out in Completely Randomized Design with four replications in each five treatments. We considered four organic solvents viz., Acetone, Methanol, Dichloromethane and Petroleum Ether along with water and observed the seed recovery percentage, germination percentage, root length, shoot length and vigour index of all the treatments. The results showed that sinker fraction regardless of organic solvent and water performed better than floater fraction. The grading ability of Dichloromethane was greater among the assessed organic solvents. The sinkers seed recovery percent of dichloromethane (93%) was higher than sinkers recovered by water (63%). Also, the sinkers of dichloromethane recorded higher germination percent(77%) and vigour index(304) than the sinkers of water whose germination percent is 55% and vigour index is 272.This specific gravity grading using dichloromethane can be adopted to segregate well filled and ill filled seeds in a seed lot of Amaranthus. This method of floatation grading is a good substitute for sieve grading which requires skilled labour and availability of specific size sieve to properly segregate seeds. So, this can be used as an alternate method for grading Amaranthus seeds.
RÉSUMÉ
An investigation entitled, “Effect of different rootstocks and scion compatibility study on Rosa sp.’’ was conducted to study the graft compatability and growth performance of grafted rose plants and the experiment was conducted in Vegetable Research Station, Tamil Nadu Agricultural University, Palur, Cuddalore district, Tamil Nadu during the year 2022. It was carried out using completely randomized design (CRD) with fifteen treatments (T1- Andhra red rose + Dog rose, T2-Andhra red rose + Button rose, T3-Andhra red rose + Ebb tide rose, T4- Andhra red rose +Fairy rose, T5- Andhra red rose + Edward rose, T6- Edward rose+ Dog rose, T7-Edward rose + Button rose, T8-Edward rose+ Ebb tide rose, T9-Edward rose + Fairy rose, T10-Edward rose+ Edward rose, T11-Damask rose + Dog rose, T12-Damask rose + Button rose, T13-Damask rose + Ebb tide rose, T14-Damask rose+ Fairy rose, T15-Damask rose+ Edward rose) and two replications. The results indicated a significant difference between the different treatment combination for graft union, success percentage, survival percentage, plant height (cm), leaf length (cm), leaf width (cm), days taken for leaf initiation. The experiment data revealed that the maximum graft success (90) and graft survival percentage (80), length of leaves (3.9 cm) and plant height (67.6) was recorded in the treatments T7 (Edward rose + Button rose). It can be concluded that the combination of rootstock as Edward rose and scion as Button rose is said to be most compatible and can be recommended for commercial cultivation.