A growth model for Trifolium subterraneum L. Swards

1978 ◽  
Vol 29 (1) ◽  
pp. 51 ◽  
Author(s):  
S Fukai ◽  
JH Silsbury
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Dry Matter ◽  
Subterranean Clover ◽  
Carbon Dioxide Exchange ◽  
Dry Matter Yield ◽  
Area Index ◽  
Crop Growth Rate ◽  
Matter Production ◽  
Final Yield

A simple deterministic model to simulate the time course of potential dry matter growth by subterranean clover swards in the field is described. Relationships used in the model were obtained mainly from experiments in temperature-controlled glasshouses and from measurements of rate of carbon dioxide exchange in an assimilation chamber. Canopy carbon dioxide exchange rates in the light and in the dark are calculated in the model from leaf area index, total dry matter, air temperature, irradiance and the crop growth rate of the sward. Photosynthates are distributed among different parts of plants according to empirical relationships. The model can estimate the potential dry matter growth of swards grown at different levels of irradiance and at different temperatures. Dry matter yield of a crop growing in the field without limitation of water and mineral nutrients can be predicted to within 20% for 100 days of growth. Potential dry matter yield of pure subterranean clover swards at Adelaide is predicted by the model to be strongly influenced by the time of cessation of growth. If the growth is terminated in the middle of October, an early start to growth as well as a high plant density will be advantageous for a high final yield. On the one hand, if the growing season extends until late November, there will be only a small effect of time of commencement of growth on final yield. The model suggests that leaf area index is an important determinant of dry matter production up to about 200 g m-2, and that increased maintenance respiration at a dry matter yield above about 600 g m-2 results in a decreased growth rate. The effects of variation in irradiance and temperature on dry matter production at different growth stages are assessed. It is concluded from use of the model that the effects of temperature on crop growth rate depend on the amount of dry matter present and on the level of solar radiation.

Effects of Plant Density on Growth and Yield of Oil Palm

1973 ◽  
Vol 9 (2) ◽  
pp. 169-180 ◽  
Author(s):  
R. H. V. Corley
Keyword(s):  
Growth Rate ◽  
Oil Palm ◽  
Dry Matter ◽  
Plant Density ◽  
Crop Growth ◽  
Growth And Yield ◽  
Area Index ◽  
Crop Growth Rate ◽  
Matter Production ◽  
Net Assimilation

SUMMARYCrop growth rate of oil palm increases with leaf area index (LAI) to about 40 tons/ha./yr at the highest LAIs obtained. Net assimilation rate and dry matter production per palm decrease with increasing LAI, but the amount of dry matter per palm incorporated in vegetative tissues is unaffected by density. As a result the optimal LAI for oil yield is considerably below the critical LAI for maximum crop growth rate.

Effects of sowing time and sowing density on the growth of subterranean clover at Adelaide

1977 ◽  
Vol 28 (3) ◽  
pp. 427 ◽  
Author(s):  
JH Silsbury ◽  
S Fukai
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Dry Matter ◽  
Plant Density ◽  
Subterranean Clover ◽  
Crop Growth ◽  
Growth Stages ◽  
Sowing Time ◽  
Area Index ◽  
Crop Growth Rate

Growth curves have been constructed for undefoliated swards of subterranean clover (cv. Woogenellup) established at three plant densities (1,2 and 4 x l03 plants per m2) at three times of the year (May, June and August). The swards grew without any apparent water stress, until early December. The time course of shoot dry matter increase is examined by the use of a logistic function and by the recognition of three growth stages. Maximum crop growth rates ranged from 10 to 15 gm-2 day-1. The rate decreased with increase in density but increased with lateness of sowing, so that the highest crop growth rate was obtained with the lowest plant density sown in August. Estimated end-of-season yields were independent of density but decreased from about 1500 g m-2 for May sowing to 1000 g m-2 for August sowing. Effects of sowing density on the growth pattern persisted throughout the whole season. Swards took 70–100 days to attain a leaf area index (LAI) of 3, after which crop growth rates were almost constant with time and independent of short-term fluctuations in the level of daily solar radiation and average daily temperature. Swards reached a maximum LAI of about 6, LAI being linearly related to the amount of shoot dry matter up to about 600 gm-2 independent of density and sowing time. No evidence was found of an optimal relationship between crop growth rate and LAI.It is concluded that end-of-season yield is independent of plant density above 1000 established plants per m2, and that swards established as late as August have the capacity to attain a yield of 10 tonnes ha-1 provided the growing season is extended.

scholarly journals Growth and yield of wheat at different dates of sowing under chrland ecosystem of Bangladesh

2017 ◽  
Vol 14 (2) ◽  
pp. 147-154 ◽  
Author(s):  
MM Kamrozzaman ◽  
MAH Khan ◽  
S Ahmed ◽  
N Sultana
Keyword(s):  
Growth Rate ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Matter ◽  
Block Design ◽  
Grain Filling ◽  
Crop Growth ◽  
Growth And Yield ◽  
Area Index ◽  
Crop Growth Rate

An experiment was conducted at Sadipur charland under Farming System Research and Development Site, Hatgobindapur, Faridpur, during rabi season of 2012-13 and 2013-14 to study the growth and yield performance of cv. BARI Gom-24 as affected by different dates of sowing under Agro-ecological Zone-12 (AEZ-12) of Bangladesh. The experiment was laid out in randomized complete block design with six replications, comprising five different dates of sowing viz. November 5, November 15, November 25, December 5 and December 15. Results reveal that the tallest plant, leaf area index, total dry matter, and crop growth rate were observed in November 25 sown crop and leaf area index, total dry matter and crop growth rate were higher at booting, grain filling, and tillering stages of the crop. Maximum effective tillers hill-1 (3.49), spikes m-2, (311), number of grains spike-1 (42.20) and 1000-grain weight (52.10 g) were produced by November 25 sown crop exhibited the highest grain (4.30 t ha-1) and straw yield (4.94 t ha-1) as well as harvest index (46.88%) of the crop. Lowest performance was observed both in early (November 5) and late sown crop (December 15). The overall results indicated that November 25 sown crop showed better performance in respect of growth and yield of wheat under charland ecosystem of Bangladesh.J. Bangladesh Agril. Univ. 14(2): 147-154, December 2016

scholarly journals Effect Of Planting Geometry On Growth Of Rice Varieties

2017 ◽  
Vol 5 (4) ◽  
pp. 423-429 ◽  
Author(s):  
Mohan Mahato ◽  
Bishnu Bilas Adhikari
Keyword(s):  
Growth Rate ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Plant Height ◽  
Dry Matter ◽  
Dry Matter Accumulation ◽  
Rice Varieties ◽  
Area Index ◽  
Crop Growth Rate ◽  
Planting Geometry

A field experiment was conducted under humid subtropical agro-climatic condition of Nepal during rainy season of 2014. The experiment was laid out in to two factor Randomized Complete Block Design with  three replications consisting three drought tolerant rice varieties (Sukhadhan-4, Sukhadhan-5 and Radha-4) and four planting geometry (15 cm × 10 cm, 15 cm × 15 cm, 20 cm × 15 cm and 20 cm × 20 cm). The results revealed that the highest plant height and maximum leaf area index was recorded in planting geometry 15 cm × 10 cm in all growth stages. Whereas, planting geometry 20 cm × 15 cm produced the maximum number of tiller m-2 in all growth stage.  While planting geometry 20 cm × 15 cm and 20 cm × 20 cm produced statistically similar crop growth rate and dry matter accumulation in all stage of growth. Regarding the varieties, Sukhadhan- 4 showed highest plant height up to 75 DAT and plant height was statistically similar to Radha - 4 in 60 and 75 DAT. But maximum number of tiller m-2, leaf area index, crop growth rate and dry matter accumulation were recorded in Sukhadhan – 5 varieties. Int. J. Appl. Sci. Biotechnol. Vol 5(4): 423-429

Evaluation of groundnut genotypes for physiological efficiencyand high yield to suit early kharif situation

2017 ◽  
Author(s):  
A. Reshma ◽  
P. Latha ◽  
V. Umamahesh ◽  
R. P. Vasanthi ◽  
P. Sudhakar
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Crop Growth ◽  
Net Assimilation Rate ◽  
Physiological Traits ◽  
Assimilation Rate ◽  
Area Index ◽  
Crop Growth Rate ◽  
Pod Yield ◽  
Net Assimilation

Groundnut is grown during July to October in kharif season, however area under early kharif (sowing in May) is increasing in Andhra Pradsh, where ever irrigation facilities exists. Hence to identify suitable variety for the situation, fourteen pre release and two released groundnut genotypes were evaluated during early kharif 2013 for growth, physiological traits and yield attributes. At harvest genotypes TCGS-1375 (41.331 g plant-1), TCGS-1342(41.059 g plant-1) significantly recorded higher total dry matter compared to all other cultivars and checks followed by TCGS-1330 (36.667 g plant-1), TCGS-1349 (36.433 g plant-1). TCGS-1342 recorded significantly higher Crop Growth Rate (CGR) value of 33.848 g m-2 day-1, where as TCGS-1346 (0.1265 g dm-2 day-1) and TCGS-1330 (0.1262 g dm-2 day-1) recorded significantly higher Net Assimilation Rate (NAR) values at 45-60 DAS. Cultivar, TCGS-1330 recorded significantly higher pod yield 4210.44 Kg ha-1 compared to other entries and checks. The results revealed that pre release genotypes, TCGS-1342, TCGS-1375, TCGS-1330, TCGS-1346 recorded high physiological efficiency in terms of growth and physiological traits viz. total dry matter (TDM), crop growth rate (CGR), net assimilation rate (NAR) and leaf area index (LAI) and also recorded high pod yield.

Changes in growth rate and morphology of perennial ryegrass swards at high and low nitrogen levels

1971 ◽  
Vol 77 (1) ◽  
pp. 123-134 ◽  
Author(s):  
Alison Davies
Keyword(s):  
Growth Rate ◽  
Perennial Ryegrass ◽  
Dry Matter ◽  
Crop Growth ◽  
Dry Matter Production ◽  
Appreciable Effect ◽  
Crop Growth Rate ◽  
Nitrogen Levels ◽  
Matter Production ◽  
Time Of Year

SummaryThe nitrogen requirements for maximum production of perennial ryegrass swards in August/September were shown to be of the order of 4 kg N/ha/day. Further increases above this level had no appreciable effect on dry-matter production, leaf area or light intercepted, but maximum tiller numbers were considerably enhanced. Shortage of nitrogenous fertilizer had comparatively little effect on crop growth rate in the early stages of regrowth, but thereafter caused the rate to fall increasingly short of potential. At high fertilizer levels crop growth rate based on total above-ground parts was linearly related to percentage light intercepted in the first month after defoliation, but values subsequently became erratic and at times negative. This change in crop growth rate and the resulting halt in effective net dry-matter production could be associated with the overall pattern of leaf and tiller formation and death, maximum net yield being achieved at the point in time when three new leaves had been produced on each tiller since cutting. It is concluded that in August and September worth-while increases in harvestable net dry matter are unlikely to occur after this stage has been reached, and that managements based on the maintenance of a complete crop cover are not likely to be successful at this time of year.

The growth and performance of cotton in a desert environment: II. Dry matter production

1969 ◽  
Vol 73 (1) ◽  
pp. 75-86 ◽  
Author(s):  
A. B. Hearn
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Initial Period ◽  
Dry Weight ◽  
Dry Matter Production ◽  
Area Index ◽  
Vegetative Phase ◽  
Matter Production ◽  
Sink Size ◽  
And Performance

SUMMARYVariety, water and spacing were treatments in two experiments with cotton in 1963 and 1964 in which fruiting points, flowers and bolls were counted and the dry weights and leaf areas of plants were measured at intervals during the season.Until leaf-area index, L, started to decrease, the equation described how dry weight, W, changed. The equation gave smoothed estimates of crop growth rate, C, which were consistent with estimates of photosynthesis made with de Wit's (1965) model. The relationship between G and L conformed to , derived from Beer's Law, rather than C = aL — bL2 derived from the linear regression of E on L. When L > 3 the crop appeared to use most of the available light, so that C approached a maximum. Treatments initially affected dry-matter production through the numbers and types of branches and nodes, which in turn affected the sinks available and thus the proportion of dry matter reinvested in new leaf. This initial period, when growth was simple to describe in conventional terms, was denned as the vegetative phase of growth.The start of the reproductive phase of growth overlapped the vegetative phase. The change from one to the other was completed when the rate of dry weight increase of the bolls, CB, equalled C. This indicated that the sink formed by the bolls had increased sufficiently in size to use all the assimilates available for growth. Sink size increased as the crop flowered and was estimated from the product of the number of bolls and the growth rate of a single boll.When CB equalled C, bolls were shed which prevented the size of the sink to increase beyond the ability of the plant to supply it with assimilates. This agrees with Mason's nutritional theory of boll shedding. Because of the crop's morphology and because age decreased the photosynthesis of the crop, the size of the sink inevitably increased out of phase with the supply of assimilates. The extent to which this was so determined when CB equalled C. It is postulated that environment, genotype and agronomic practice affect yield according to whether they increase or decrease the extent to which the sink size and the supply of assimilates are out of phase.

scholarly journals Characterization of Dry Matter Partition with Grain Yield in Advanced Breeding Lines of Rice (Oryza sativa L.)

2020 ◽  
pp. 51-60
Author(s):  
D. Dev Kumar ◽  
D. Vishnu Vardhan Reddy ◽  
P. Raghuveer Rao ◽  
M. Sheshu Madhav ◽  
V. Gouri Shankar
Keyword(s):  
Growth Rate ◽  
Grain Yield ◽  
Photosynthetic Rate ◽  
Dry Matter ◽  
Crop Growth ◽  
Area Index ◽  
Crop Growth Rate ◽  
Breeding Lines ◽  
Leaf Weight ◽  
Initiation Stage

The experimental field was laid in RBD replicated thrice with 30 high yielding rice genotypes which includes 26 advanced breeding lines (ABL) (SP-351, SP-352, SP-353, SP-354, SP-355, SP-356, SP-357, SP-358, SP-359, SP-360, SP-70, SP-72, SP-63, SP-61, SP-69, SP-55, SP-80, SP-25, SP-13,  SP-03, SP-02, SP-34, SP-37, SP-08, SP-75 and SP-57) and four checks (NDR-359, BPT-5204, IR-64, Jaya). Seven genotypes showed significantly higher leaf weight over the BPT-5204. Further, leaf weight at panicle initiation stage showed a positive relationship with TDM (Total Dry Matter) (r=0.51**). At the panicle initiation stage, only three genotypes (SP-354, SP-358, and SP-72) were superior to BPT-5204 in leaf weight. The shoot biomass and total dry weight was superior only in one genotype SP-72 as compared to BPT-5204. Similarly, the net assimilation rate at panicle initiation stage was maximum in SP-08 (9.92g m-2 day-1) and SP-72 (9.35g m-2 day-1) as compared to check BPT-5204 (6.47g m-2 day-1). These genotypes maintained higher photosynthetic rate (SP-72) and higher grain yield (SP-08). The relationship between CGR (Crop Growth Rate) and TDM (Total Dry Matter) and grain yield (r=0.61**) was positive and significant at physiological maturity. Genotypes SP-08 and SP-72 showed significantly higher CGR (Crop Growth Rate) over BPT-5204 and hence, yielded higher. In the present study compared to BPT-5204, genotypes SP-72, SP-08 maintained higher lea area index at all crop growth stages. These genotypes maintained higher photosynthetic rate (SP-72) and higher grain yield (SP-08). Positive significant relationship between LAI (Leaf Area Index) and total dry matter at harvest and; grain yield has been observed.

scholarly journals EFFECT OF SEEDS SOAKING AND VEGETATIVE PARTS NUTRITION WITH ACIDS OF ASCORBIC, CITRIC AND HUMIC ON MAIZE GROWTH

2021 ◽  
Vol 52 (5) ◽  
pp. 1207-1218
Author(s):  
J. J. Kadhim ◽  
J. H. Hamza
Keyword(s):  
Growth Rate ◽  
Humic Acid ◽  
Dry Matter ◽  
Block Design ◽  
Crop Growth ◽  
Control Treatment ◽  
Distilled Water ◽  
Area Index ◽  
Crop Growth Rate ◽  
Dry Matter Weight

A field experiment was carried out during two spring seasons in 2019 and 2020. This study was aimed to increase dry matter weight and crop growth rate of maize. First factor in main plots was nutrition vegetative parts with ascorbic and citric (100 mg l-1) for both of them and humic (1 ml l-1), in addition to the control treatment (spraying of vegetative parts with distilled water only). Second factor in sub-plots was seeds soaking with same acids above, as well as the control treatment (soaking the seeds with distilled water only). Randomize complete block design in split plot arrangement was used with three replications. The results showed a significant superiority of seeds soaking in humic acid for traits of number of days from planting to 75% anthesis  and silking (66.4 and 66.3 day) and (72.3 and 72.3 day), plant height (194.0 and 230.8 cm), leaves area plant-1 (6969.5 and 6570.2 cm2), leaf area index (3.71 and 3.50), dry matter weight (11.6 and 12.2 ton ha-1), crop growth rate (3.0 and 3.2 g cm-2 day-1) and chlorophyll leaf content (60.2 and 69.5 SPAD) for both seasons, respectively. Effect of vegetative parts nutrition and interaction effect of both studied factors was non-significant for most traits. It can be concluded that seeds soaking in humic acid improved growth traits. It can be recommended to soak seeds of maize before planting in humic acid at concentration of 1 ml l-1.

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