scholarly journals Photosynthetic Evaluation of Sweetpotato Germplasm

1990 ◽  
Vol 115 (4) ◽  
pp. 634-639 ◽  
Author(s):  
Ajmer S. Bhagsari
Keyword(s):  
Stomatal Conductance ◽  
Harvest Index ◽  
Dry Matter ◽  
Photosynthetic Efficiency ◽  
The Other ◽  
Storage Root ◽  
Canopy Photosynthesis ◽  
Root Yield ◽  
Area Index ◽  
Final Harvest

Field experiments were conducted from 1980-1983 to evaluate sweetpotato [Ipomoea batatas (L.) Lam.] germplasm for photosynthetic efficiency, harvest index [HI; (storage root dry matter/total plant dry matter) × 100], and yield. Most genotypes maintained leaf area index (LAI) above five until final harvest, 164 days after planting (DAP). The higher LAI (> 8) for PI 318859, PI 344134, and PI 308205 compared to the other genotypes was maintained at the expense of the storage root development. Single leaf net photosynthesis (Pn) of the genotypes ranged from 0.61 to 1.09 mg CO2/m2 per sec during 1980. Canopy photosynthesis on a ground area (CPn-Ga) basis ranged from 0.95 to 1.56 and 1.04 to 1.30 mg CO2/m2 per sec during July and August 1983, respectively. Canopy photosynthesis expressed on leaf dry-weight (CPn-Dwt) basis was higher for PI 344122 than the other genotypes, except PI 344138, indicating its superior photosynthetic efficiency. Photosynthetic efficiency and stomatal conductance were not related to yield. Stomatal conductance and CPn-Ga were significantly correlated. Harvest index differed significantly at each sampling and ranged from 14.0% to 75.5% at final harvest. Fresh storage root yield for 1983 and 4-year mean yield ranged from 8.6 to 60.1 and 14.1 to 42.2 t·ha-1 respectively. At final harvest, HI correlated significantly with fresh-(r = 0.91) and dry-matter storage root yield (r = 0.95). Despite significant photosynthetic variations among the genotypes, sweetpotato yield was influenced more by HI and storage root sink strength than by photosynthetic efficiency.

scholarly journals Relationship of Photosynthesis and Harvest Index to Sweet Potato Yield

1990 ◽  
Vol 115 (2) ◽  
pp. 288-293 ◽  
Author(s):  
Ajmer S. Bhagsari ◽  
Doyle A. Ashley
Keyword(s):  
Sweet Potato ◽  
Harvest Index ◽  
Ipomoea Batatas ◽  
Field Experiments ◽  
Storage Root ◽  
Canopy Photosynthesis ◽  
Storage Roots ◽  
Physiological Basis ◽  
Area Index ◽  
Stage Of Development

Field experiments with 15 sweet potato [Ipomoea batatas L. (Lam.)] genotypes were conducted to study the physiological basis of yield in 1981 and 1982. The leaf area index differed significantly among the sweet potato genotypes during early and late phases of growth, hut showed an inconsistent relationship with yield. Single leaf net photosynthesis ranged from 0.74 to 1.12 mg CO2/m' per sec. Canopy photosynthesis for sweet potato genotypes differed significantly in 1981, but not in 1982. It ranged from 0.81 to 1.16 mg CO2/m2 per sec in Aug. 1981. and from 0.63 to 0.88 mg CO2/m2 per sec in 1982. Four hours after “C-labeling, 14C-assimilate translocation from the treated leaf ranged from 21% to 46%, but did not differ significantly among the genotypes. At final harvest, harvest index [HI, defined as (storage root yield/total biological yield) × 100] of the genotypes varied from 43% to 77% and 31% to 75% for 1981 and 1982, respectively. Canopy photosynthesis during September was significantly correlated with storage root dry matter yield (r = 0.54*) in 1981 and with phytomass (above-ground biomass plus storage roots) (r = 0.60*) in 1982. Both phytomass and HI were significantly correlated with storage root matter yield. Canopy photosynthetic evaluation of sweet potato germplasm may be-more relevant when the storage root sinks are at an advanced stage of development. Our study suggests that yield is poorly predicted by Pn, particularly when the genotypes have different leaf sizes.

A comparison of barley cultivars with different leaf inclinations

1972 ◽  
Vol 23 (6) ◽  
pp. 945 ◽  
Author(s):  
JF Angus ◽  
R Jones ◽  
JH Wilson
Keyword(s):  
Dry Matter ◽  
Canopy Structure ◽  
The Other ◽  
Dry Matter Production ◽  
Visible Radiation ◽  
Area Index ◽  
Assimilation Chamber ◽  
Barley Cultivars ◽  
Matter Production ◽  
Erect Leaf

Under conditions of adequate moisture an erect-leaf barley cultivar, Lenta, responded to an increase in density (resulting from doubling of the sowing rate) with increases in dry matter production and in grain yield, whereas the cultivar Research, which has long lax leaves, responded with decreases in dry matter production and yield. In a study of canopy structure and its effects on light interception and utilization, it was found that in Research, with a leaf area index (LAI) of 6.1, the leaves were concentrated near the canopy surface and a relatively small proportion of the above-crop light penetrated through this layer. The net crop photosynthesis of this canopy (measured in a field assimilation chamber) was 3.8 g CO2/m2.hr when visible radiation was 313 W/m2. With Lenta (LAI 7.0) on the other hand, leaves were concentrated in the middle layers of the canopy and the light was more evenly distributed throughout the canopy. The net crop photosynthesis with the same radiation as for Research was 4.3 g CO2/m2.hr. The relative rates of photosynthesis at various levels in the canopies were determined by introducing 14CO2 into the assimilation chambers enclosing the cultivars and observing where the 14C was fixed. With Research most of it was localized near the canopy surface while with Lenta most of it was near the centre of the canopy. Of the 14CO2 taken up, 7 % was fixed in the leaf sheaths of Research and 12% in those of Lenta.

scholarly journals Correlation Studies in Ashwagandha [Withania somnifera (L.) Dunal]

2021 ◽  
pp. 58-64
Author(s):  
Babulal Dhaka ◽  
Amit Dadheech ◽  
N. K. Padiwal ◽  
Raju Ram Choudhary
Keyword(s):  
Harvest Index ◽  
Withania Somnifera ◽  
Root Diameter ◽  
Root Yield ◽  
Area Index ◽  
Plant Weight ◽  
Correlation Studies ◽  
Collar Region ◽  
Fresh Plant ◽  
Fresh Root

In the present study entitled “Variability and Correlation Studies in Ashwagandha [Withania somnifera (L.) Dunal]”, 74 genotypes along with three standard checks viz., JA-20 (Jawahar Asgandh-20), JA-134 (Jawahar Asgandh-134) and RVA-100 were evaluated in augmented RBD design during late kharif 2019-20 at the Instructional Farm, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan). The observations were recorded on ten randomly selected competitive plants for fifteen characters, viz. days to 50% flowering, days to 75 per cent maturity, plant height, number of primary branches per plant, number of secondary branches per plant, leaf area index, root length, root diameter in collar region, fresh root yield per plant, dry root yield per plant, fresh plant weight per plant, dry plant weight per plant, 100 seed weight, harvest index and total alkaloid. Analysis of variance, correlation coefficient and path analysis were performed for the mean data. The dry root yield per plant exhibited significant and positive correlation with dry plant weight, fresh root yield and harvest index at both genotypic and phenotypic level. While with, root diameter in collar region at genotypic level and fresh plant weight at phenotypic level. Positive and significant correlation among dry root yield per plant and contributing characters would help in indirect selection for dry root yield per plant in the crop like ashwagandha where economic part (dry root yield per plant) remain underground up till uprooting.

scholarly journals Adaptation to mid-season drought in a sweetpotato (Ipomoea batatas [L.] Lam) germplasm collection grown in Mozambique

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Godwill S. Makunde ◽  
Maria I. Andrade ◽  
Jose Ricardo ◽  
Abilio Alvaro ◽  
Joana Menomussanga ◽  
...  
Keyword(s):  
Drought Tolerance ◽  
Harvest Index ◽  
Ipomoea Batatas ◽  
Block Design ◽  
Geometric Mean ◽  
Germplasm Collection ◽  
High Yield ◽  
Research Station ◽  
Storage Root ◽  
Root Yield

AbstractDrought has negative effects on sweetpotato production. Two experiments with two watering treatments (irrigated and water-stressed) were conducted at Umbeluzi Research Station in 2015. The objectives were to (i) determine response of 48 sweetpotato germplasms to mid-season drought, (ii) determine best traits for improvement of storage root yield under mid-season drought and (iii) assess the selection criteria for identifying drought tolerance in sweetpotato germplasms. The irrigated and water- stressed trials received 640 and 400 mm of water, respectively, throughout the season. Water stress was imposed from 30 to 70 days after planting. Each treatment had two replicates arranged in a randomized complete block design. Data collected on storage root and vine yield and derived drought tolerance indices including harvest index were subjected to analysis of variance in R. Sweetpotato germplasms with high storage root yield under mid-season drought were associated with a high harvest index. Harvest index stability and the geometric mean are key to identifying cultivars with high and stable storage root yield under both treatments. MUSGP0646-126, Irene and Ivone combined both low TOL, SSI, HI and high yield storage root yield across the treatments and over seasons. The use of drought and harvest indices is encouraged for selecting improved cultivars for varied production environments and their regular use in accelerated breeding schemes is suggested.

scholarly journals Combining Ability, Heterosis, and Heritability of Storage Root Dry Matter, Beta-Carotene, and Yield-related Traits in Sweetpotato

HortScience ◽  
2018 ◽  
Vol 53 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Fekadu Gurmu ◽  
Shimelis Hussein ◽  
Mark Laing
Keyword(s):  
Combining Ability ◽  
Dry Matter ◽  
Breeding Value ◽  
Dry Matter Content ◽  
Storage Root ◽  
Root Yield ◽  
Carotene Content ◽  
Positive Heterosis ◽  
High Storage ◽  
Β Carotene

Orange-fleshed sweetpotato (OFSP) is an effective, low-priced, and sustainable source of β-carotene (provitamin A). However, most OFSP varieties have low storage root dry matter content (DMC), which influences their acceptance by small-scale farmers and hence needs to be improved. The objective of the study was to determine the combining ability, type of gene action, heterosis and heritability of storage root DMC, β-carotene content, and yield-related traits of selected sweetpotato clones for further evaluation and breeding. Crosses were conducted using a 7 × 7 half-diallel mating design and a total of 28 genotypes (seven parents and 21 crosses) were evaluated at four locations in Ethiopia using a 7 × 4 alpha lattice design with two replications. The performance of the genotypes was significantly different (P < 0.01) across the four locations for storage root DMC, β-carotene content, sweetpotato virus disease (SPVD) reaction, storage root yield, and harvest index (HI). The general combining ability (GCA) and specific combining ability (SCA) mean squares were significant (P < 0.01) for all traits except the SCA effect of storage root DMC. The GCA to SCA variance ratios were 0.96, 0.94, 0.74, 0.96, and 0.97 for storage root DMC, β-carotene content, SPVD, fresh storage root yield, and HI, respectively, indicating that the inheritance of these traits was controlled mainly by additive genes. Progenies of crosses involving Ukerewe × Ejumula, Ukerewe × Pipi, Resisto × Pipi, and Ejumula × Pipi exhibited high levels of positive heterosis for storage root DMC. Similarly, progenies of crosses including Resisto × Pipi and Resisto × Ogansagan had higher positive heterosis for fresh storage root yield, reflecting the breeding value of these parents. Relatively high narrow sense heritability (h2) was obtained for β-carotene content (79.8%) and HI (48.6%). However, the h2 estimates of storage root DMC, SPVD, and fresh storage root yield were relatively low at 19.0%, 14.9%, and 20.4%, respectively. Crosses with high β-carotene content such as Ukerewe × Resisto, Resisto × Ogansagan, Eumula × Pipi, and NASPOT 1 × Temesgen exhibited high storage root DMC. These families also had medium-to-high mean fresh storage root yield. Therefore, progenies derived from these families are good candidates to develop improved OFSP varieties with high storage root DMC.

scholarly journals The Physiological Basis for Yield Differences between Four Genotypes of Groundnut (Arachis Hypogaea) in Response to Drought. I. Dry Matter Production and Water Use

1988 ◽  
Vol 24 (2) ◽  
pp. 191-202 ◽  
Author(s):  
R. B. Matthews ◽  
D. Harris ◽  
R. C. Nageswara Rao ◽  
J. H. Williams ◽  
K. D. R. Wadia
Keyword(s):  
Water Availability ◽  
Harvest Index ◽  
Dry Matter ◽  
Central India ◽  
The Other ◽  
Soil Water Depletion ◽  
Physiological Basis ◽  
Matter Production ◽  
Tap Root ◽  
Major Variation

SUMMARYFour genotypes of groundnut grown with limited irrigation in a medium depth Alfisol in Central India transpired similar total amounts of water (220–226 mm) over the season, but produced different amounts of shoot dry matter (390–490 g m−2). The extraction front of Kadiri 3 moved most rapidly down the soil profile which may have enabled it to maintain the fastest rates of transpiration when soil water depletion was greatest. Tap root extension rates of Kadiri 3 in the first 32 days after sowing were also the fastest. NC Ac 17090 was more efficient than the other genotypes in extracting water immediately after irrigation from the upper 40 cm of the soil, but this had little value in determining the pattern of water availability in this experiment. Differences in the water extraction characteristics of these genotypes explain little of the variation in dry matter:water ratio, and do not account for the major variation in harvest index associated with drought.

Analysis of the regrowth of a tropical grass/legume sward subjected to different frequencies and intensities of defoliation

1980 ◽  
Vol 31 (4) ◽  
pp. 673 ◽  
Author(s):  
MM Ludlow ◽  
DA Charles-Edwards
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Dry Weight ◽  
Light Interception ◽  
Photosynthetic Characteristics ◽  
Dry Matter Production ◽  
Canopy Photosynthesis ◽  
Area Index ◽  
Matter Production ◽  
Cutting Height

Dry weight, leaf area, light interception and canopy photosynthesis were measured during 3- or 5-week regrowth periods of Setaria anceps/Desmodium intortum swards cut to 7.5 or 15 cm. Dry matter production during the experiment and over the growing season increased with cutting height and with interval between defoliations, but the proportion of grass to legume was unaffected. These effects of defoliation on dry matter production were similar to those estimated for integrated canopy photosynthesis from measured light interception and calculated leaf photosynthetic characteristics. Height and frequency of defoliation had no effect on canopy extinction coefficient for light, nor on the leaf photosynthetic characteristics, except for the first 1-2 weeks after defoliation when leaf photosynthetic rates appeared to be depressed. The main effects of height and frequency of defoliation on dry matter production were through their effects on leaf area index and light interception.

scholarly journals Responses of Canola to Different Row and Plant Spacings

2000 ◽  
Vol 5 (2) ◽  
pp. 69
Author(s):  
M.A. Cheema ◽  
M.A. Malik ◽  
A. Hussain ◽  
S.H. Shah ◽  
S.M.A. Basra
Keyword(s):  
Brassica Napus ◽  
Field Study ◽  
Harvest Index ◽  
Dry Matter ◽  
Growth And Yield ◽  
Oil Yield ◽  
Row Spacing ◽  
Plant Spacing ◽  
Brassica Napus L ◽  
Area Index

A field study was carried out to determine growth and yield of canola (Brassica napus L.) at different inter row (30, 45, and 60 cm) and intra row (10, 15, and 20 cm) spacing between 1995-97. The closer row Spacing of 30 cm significantly increased leaf area index (LAD, total dry matter (TDM) in both the seasons over wider spacing of 45 and 60 cm. Similarly closer plant spacing of 10 cm also enhanced LA! and TDM over 15 or 20 cm plant spacing. Seed and oil yield was significantly increased in first row spacing compared with 45 or 60 cm row spacing in both seasons. Swd yield was linearly related to TDM yield, harvest index was not changed. The results suggest that closer spacing of 30 cm is optimum for maximizing seed and oil yield for canola under the agro-ecological conditions of Faisalabad.  

scholarly journals Morphological Variability and Storage Root Productivity of Some Sweet Potato (Ipomoea Batatas (L.) Lam) Genotypes in An Ultisol

2021 ◽  
Vol 2 (6) ◽  
Author(s):  
Gamaliel I. Harry ◽  
Joseph I. Ulasi
Keyword(s):  
Principal Component Analysis ◽  
Sweet Potato ◽  
Ipomoea Batatas ◽  
Principal Component ◽  
Component Analysis ◽  
The Other ◽  
Storage Root ◽  
Root Yield ◽  
Cropping Seasons ◽  
And Storage

Ten sweet potato (Ipomoea batatas (L.) Lam) genotypes sourced from National Root Crops Research Institute, Umudike were evaluated under rainfed condition in 2020 and 2021 cropping seasons at the Teaching and Research Farm of the University of Uyo, Uyo, Akwa Ibom State to ascertain variability among ten sweet potato genotypes and identify traits which are positively and significantly associated with yield and also identify genotypes with high yield potential for cultivation on an ultisol of Akwa Ibom State, Nigeria. The ten genotypes: TIS87/0087, Naspoy-12, Umuspo-4, Umuspo-1, Naspoy-11, Lourdes, Erica, Delvia, Ex-Igbariam and Umuspo-3 were used as treatments and the experiment was laid out in a randomized complete block design with three replications. Data collected were subjected to analysis of variance, correlation and principal component analysis. The genotype differs significantly (P≤ 0.05) for number of marketable roots, weight of marketable roots and fresh roots yield. UMUSPO-3 was superior over all the other genotypes for the following character; number of marketable roots, weight of marketable root yield and fresh root yield. Umuspo-3 produced the highest storage root yield (28.78t/ha, 27.09t/ha) in 2020 and 2021 cropping seasons, respectively. The result of the correlation analysis also revealed that vine length, number of marketable roots, weight of marketable were highly significantly and positively (P<0.01) correlated with fresh root yield. Principal component analysis (PCA) had four main principal components explaining 81.55% of the total variation with number of marketable roots, weight of marketable tuber and storage root yield contributing the most to the first PCA. Umuspo-3 outperformed the other nine sweet potato genotypes in yield and yield related characters. Therefore, Umuspo-3 been a high yielding genotype adaptable to Uyo agro-ecology, could be recommended to sweet potato growers for fresh storage root production.

Sign in / Sign up

Export Citation Format

Share Document