Investigations on Seedling Vigour in Cashew (Anacardium occidentale L.)

Abstract

Seedlings from 27 open pollinated cashew genotypes in two environments with five replications in each location were used to investigate the genetic, the environmental, and the nut size effects on cashew seedling vigour during the 12-week pretransplantation period.Environmental variances, genotype X environment interactions, and broadsense heritability values for the eight studied traits indicated that emergence percentage (E %J and seedling height (SH) were more reliable indices for seedling vigour, since they were more heritable and less influenced by the environment. Seedlings from large cashew nuts were consistently more vigorous than those from small nuts, probably because of the larger food reser\'e in the two cotyledons.Key words: Anacardiiim occidentale -seedling vigour -emergence percentage -surv^ival percentage -vegetative traits RAO ei al. (i957a, b), IBIKUNLE and KOMOLAFE (1973) and ROMOLAFE (1975) reported their research findings concerning viability of cashew nuts. TURNER (1956) showed that cashew nuts of greater density germinated more quickly than nuts of lower density. iBikL' NLi-. and KoMOL.Af' E recommended that cashew nuts which sank m water prior to sowing should be used in raising cashew seedlings and that cashew nuts should be soaked in water for 24 hours before sowing. These authors showed that nut size was an important factor in the germination of cashew nuts and that very small nuts weighing about 2.00 g would give a satisfactory germination. The experiments conducted by these authors were all on cashew germination and nothing was done concerning other important indicators of seedling vigour, such as, seedling stem girth, seedling height, leaf area and drv-matter accumulation by the seedlings.High emergence percentage (E %) which defines nut vigour or nut viability and high percentage needling survival (S %) followed by adequate vegetative vigour are of major importance for successful stand establishment in farm crops. Thus, selection for seedling vigour indicators should always be considered in any breeding programme designed to improve a crop species. For instance, many cashew plantations in Nigeria have poor cashew tree stands probably because of low vegetative vigour ol the seedlings. It is desirable, therefore, to investigate the extent to which the seedling vigour factors are genetically and environtnentally controlled. These investigations would help considerably in our efforts to select the right nut size, the right genotype and the right cnvironrnent for U.S. Copynsh. Ckar..nce C.nc.r Code St.u-m.n.: 01 79-9541/86/9703-0237$02.50/0

Effects of Seed Size on Germination and Early Morphorlogical and Physiological Characteristics of <I>Gmelina Arborea</I>, Roxb

“…On the other hand, the lower germination obtained from small sized seeds could be attributed to relatively lower food reserve in the small sized seeds, the stage of maturity, size of the cotyledon and genetics factors. This finding agrees with the observations of Faluyi (1986), who reported better growth in cashew (Anacadium accidentale) from large nuts than small nuts. Oni and Bada (1992) also reported that seed from large nuts showed better germination and growth than seeds from small nuts.…”

Effects of Seed Size on the Germination and Early Growth of African Baobab (Adansonia digitata L.)

“…On the other hand, the low germination percentage of the small seeds could be attributed to relatively lower food reserve in a small-sized seeds, the stage of maturity, and size of cotyledon and genetic factors. This finding agrees with the report of Faluyi [13], who noted better growth in cashew from large nuts than small nuts. Bada [14] reported that seeds size can be used as a parameter for predicting germination and seedling growth rate both in the nursery and the brief period following establishment.…”

Effect of Crude Oil-Contaminated Soil on Germination and Growth Performance of &lt;i&gt;Abelmoschus esculentus&lt;/i&gt; L. Moench—A Widely Cultivated Vegetable Crop in Nigeria

“…The seedling emergence in the treatments and the control experiment was observed and recorded. Seedling emergence percentage in each treatment was calculated, according to [9] as:…”