scholarly journals Interactive Effects of Sowing Date and Planting Density on Dry Matter Accumulation and Partitioning of Chicory

2012 ◽  
Vol 40 (1) ◽  
pp. 183
Author(s):  
Hamid MADANI ◽  
Christos DORDAS ◽  
Ahad MADANI ◽  
Mohammad-Ali MOTASHAREI ◽  
Shima FARRI

Chicory is considered one of the alternatives crops that can be used in crop rotation and contains many phytochemicals that can be used in medicine. In addition, lengthening the growing season by early sowing may increase root chicory yield potential, and thus increase its competitiveness with traditional crops. The objectives of the present study were to determine whether early sowing date risks can be decreased by higher sowing density and also to study the effect of sowing date and sowing density on dry matter accumulation and partitioning of chicory. Growing season did not affect any of the characteristics that were studied. Also plant density affected the flowers biomass, root biomass per plant and the respective yield together with the plant height and essence yield and total yield. The sowing date affected the leaf, flower and stem biomass on a plant basis. However, the interaction between plant density and sowing date affected the total biomass per plant, the flower biomass per plant, the root biomass per plant, the flower yield, the root yield and the essence yield. These results indicate that for higher production it is important to determine the right plant density and sowing date which can affect growth, dry matter accumulation and essence yield.

2007 ◽  
Vol 58 (1) ◽  
pp. 21 ◽  
Author(s):  
Heping Zhang ◽  
Neil C. Turner ◽  
Michael L. Poole ◽  
Senthold Asseng

The growth and yield of spring wheat (Triticum aestivum L.) were examined to determine the actual and potential yields of wheat at a site in the high rainfall zone (HRZ) of south-western Australia. Spring wheat achieved yields of 5.5−5.9 t/ha in 2001 and 2003 when subsurface waterlogging was absent or minimal. These yields were close to the estimated potential, indicating that a high yield potential is achievable. In 2002 when subsurface waterlogging occurred early in the growing season, the yield of spring wheat was 40% lower than the estimated potential. The yield of wheat was significantly correlated with the number of ears per m2 (r2 = 0.81) and dry matter at anthesis (r2 = 0.73). To achieve 5–6 t/ha of yield of wheat in the HRZ, 450–550 ears per m2 and 10–11 t/ha dry matter at anthesis should be targetted. Attaining such a level of dry matter at anthesis did not have a negative effect on dry-matter accumulation during the post-anthesis period. The harvest index (0.36−0.38) of spring wheat was comparable with that in drier parts of south-western Australia, but relatively low given the high rainfall and the long growing season. This relatively low harvest index indicates that the selected cultivar bred for the low- and medium-rainfall zone in this study, when grown in the HRZ, may have genetic limitations in sink capacity arising from the low grain number per ear. We suggest that the yield of wheat in the HRZ may be increased further by increasing the sink capacity by increasing the number of grains per ear.


2011 ◽  
Vol 36 (12) ◽  
pp. 2143-2153 ◽  
Author(s):  
Xiang-Ling LI ◽  
Ming ZHAO ◽  
Cong-Feng LI ◽  
Jun-Zhu GE ◽  
Hai-Peng HOU ◽  
...  

1979 ◽  
Vol 30 (5) ◽  
pp. 815 ◽  
Author(s):  
AD Doyle ◽  
RA Fischer

In order to better understand crop growth (dry matter accumulation, DM), crop evapotranspiration (Et), and their interrelationships, we studied dryland crops of wheat (Triticum aestivum L. cv. Timgalen) sown at various dates and seeding densities in each of three years at Tamworth, N.S.W. Soil water stress was minimal before anthesis in each year, but in two years substantial stress arose before maturity. DM was increased consistently by increased plant density, and decreased at anthesis and maturity by later sowing. Crop growth rates determined over 2-week intervals around anthesis ranged from 3 to 20 g m-2 d-1, representing a range in efficiency of utilization of intercepted total solar radiation of 0.48 to 2.35%, variation which was adequately explained (R2 = 0.80) by ontogeny (days from anthesis) and Et / Ep ratio (Ep = class A pan evaporation). Et at anthesis, but not at maturity, was increased slightly by higher seedmg density; crop Et was not consistently affected by sowing date. Et / Ep over 2-week periods around anthesis was related to leaf area index, and to a lesser extent to available soil water and Ep (R2 = 0.58). For the period from the first sowing date in June or July until the middle of October, the relationship of total Et to DM production was linear and close each year, but the slope varied from 6.2 g m-2 mm-1 (cold dry year) to 14.0 g m-2 mm-1 (wet year). This variation could be attributed to annual variation in the soil evaporation component of Et, and in the ratio of DM to crop transpiration (= transpiration efficiency, TE). For 2-week periods around anthesis, TE ranged from 2.9 to 5.4 g m-2 mm-1 and was inversely related to Ep (R2 = 0.56). Provided soil evaporation can be allowed for, since it ranged from 18 to 41% of crop Et from sowing to maturity, it is argued that the crop transpirationtranspiration efficiency approach is particularly useful for analysing the growth and water use of dryland wheat.


1996 ◽  
Vol 127 (2) ◽  
pp. 183-191 ◽  
Author(s):  
I. Shield ◽  
H. J. Stevenson ◽  
J. E. Leach ◽  
T. Scott ◽  
J. M. Day ◽  
...  

SUMMARYThe effects of varying the sowing date (early September-late October) and plant density (14–70 seeds/m2) on the establishment, overwinter survival, structure and yield of an autumn-sown, florallydeterminate line (CH304/70) of the white lupin (Lupinus albus) were examined in three contrasting growing seasons between 1991 and 1994. Crops established well when sown in early September and were sufficiently cold-hardy to survive prolonged and extremely severe early winter frosts, but crops sown in late October either lost many plants or were destroyed completely. There was a strong interaction between sowing date and autumn weather on crop structure and yield. Late sowing and cold autumn weather restricted the number of mainstem leaves and first-order lateral branches on the plant, and decreased plant height and yield potential.Despite considerable differences between years in the weather during the summer and autumn, all crops were harvested in early September. Grain yields ranged from 0·3 to 4·5 t/ha depending on season, sowing date and plant density. Yields were strongly correlated with the number of podbearing axes and pods per m2 and, although actual yields differed depending on growing conditions, the same number of pod-bearing axes (100/m2) was required in each year to achieve maximum yield. The effects of sowing date and autumn weather on plant structure were well predicted by a simple developmental model that related vernalization and leaf development to post-sowing temperature.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 523c-523
Author(s):  
Siegfried Zerche

Refined nutrient delivery systems are important for environmentally friendly production of cut flowers in both soil and hydroponic culture. They have to be closely orientated at the actual nutrient demand. To solve current problems, express analysis and nutrient uptake models have been developed in horticulture. However, the necessity of relatively laborious analysis or estimation of model input parameters have prevented their commercial use up to now. For this reason, we studied relationships between easily determinable parameters of plant biomass structure as shoot height, plant density and dry matter production as well as amount of nitrogen removal of hydroponically grown year-round cut chrysanthemums. In four experiments (planting dates 5.11.91; 25.3.92; 4.1.93; 1.7.93) with cultivar `Puma white' and a fixed plant density of 64 m2, shoots were harvested every 14 days from planting until flowering, with dry matter, internal N concentration and shoot height being measured. For each planting date, N uptake (y) was closely (r2 = 0.94; 0.93; 0.84; 0.93, respectively) related to shoot height (x) at the time of cutting and could be characterized by the equation y = a * × b. In the soilless cultivation system, dry matter concentrations of N remained constant over the whole growing period, indicating non-limiting nitrogen supply. In agreement with constant internal N concentrations, N uptake was linearly related (r2 = 0.94 to 0.99) to dry matter accumulation. It is concluded that shoot height is a useful parameter to include in a simple model of N uptake. However, in consideration of fluctuating greenhouse climate conditions needs more sophisticated approaches including processes such as water uptake and photosynthetically active radiation.


Author(s):  
Muhammad Zeeshan Mehmood ◽  
Ghulam Qadir ◽  
Obaid Afzal ◽  
Atta Mohi Ud Din ◽  
Muhammad Ali Raza ◽  
...  

AbstractSeveral biotic and abiotic stresses significantly decrease the biomass accumulation and seed yield of sesame crops under rainfed areas. However, plant growth regulators (such as Paclobutrazol) can improve the total dry matter and seed production of the sesame crop. The effects of the paclobutrazol application on dry matter accumulation and seed yield had not been studied before in sesame under rainfed conditions. Therefore, a two-year field study during 2018 and 2019 was conducted with key objectives to assess the impacts of paclobutrazol on leaf greenness, leaf area, total dry matter production and partitioning, seed shattering, and seed yield of sesame. Two sesame cultivars (TS-5 and TS-3) were treated with four paclobutrazol concentrations (P0 = Control, P1 = 100 mg L−1, P2 = 200 mg L−1, P3 = 300 mg L−1). The experiment was executed in RCBD-factorial design with three replications. Compared with P0, treatment P3 improved the leaf greenness of sesame by 17%, 38%, and 60% at 45, 85, and 125 days after sowing, respectively. However, P3 treatment decreased the leaf area of sesame by 14% and 20% at 45 and 85 days after sowing than P0, respectively. Compared with P0, treatment P3 increased the leaf area by 46% at 125 days after sowing. On average, treatment P3 also improved the total biomass production by 21% and partitioning in roots, stems, leaves, capsules, and seeds by 23%, 19%, 23%, 22%, and 40%, respectively, in the whole growing seasons as compared to P0. Moreover, under P3 treatment, sesame attained the highest seed yield and lowest seed shattering by 27% and 30%, respectively, compared to P0. This study indicated that by applying the paclobutrazol concentration at the rate of 300 mg L−1 in sesame, the leaf greenness, leaf areas, biomass accumulation, partitioning, seed yield, and shatter resistance could be improved. Thus, the optimum paclobutrazol level could enhance the dry matter accumulation and seed production capacity of sesame by decreasing shattering losses under rainfed conditions.


2003 ◽  
Vol 51 (1) ◽  
pp. 25-35 ◽  
Author(s):  
A. Y. Allam ◽  
G. R. El-Nagar ◽  
A. H. Galal

This investigation was carried out at the Experimental Farm of Assiut University during the summers of 2000 and 2001 to study the responses of two sunflower hybrids (Vidoc and Euroflora) to planting dates (May 1st, June 1st and July 1st) and planting densities (55,533, 83,300 and 166,600 plants/ha). The results indicated that the two varieties differed highly significantly in all studied traits except oil yield/ha. The highest seed yield (3.64 t/ha) was obtained with the variety Vidoc. In addition, the results revealed that the planting date exerted a highly significant influence on all vegetative growth traits along with yield and its components. Increasing plant density increased the seed and oil yield/ha. By contrast, the stem diameter, head diameter, 100-seed weight and seed yield/plant decreased with increasing plant density. The interaction between varieties and plant density had a highly significant effect on head diameter. The greatest head diameter (20.06 cm) was recorded for the variety Vidoc planted at lower density. Concerning the interaction between planting density and planting date, the highest seed yield (4.47 t/ha) was obtained from dense plants at the early sowing date, and the highest oil % (45.32) at the late planting date and the lowest plant density. The second order interaction exerted a highly significant influence on stem and head diameter in addition to seed yield/plant, where the highest value (78.13 g/plant) was obtained with the variety Vidoc planted on May 1st at the lowest plant density.


HortScience ◽  
2019 ◽  
Vol 54 (12) ◽  
pp. 2169-2177 ◽  
Author(s):  
Karen Mesa ◽  
Sara Serra ◽  
Andrea Masia ◽  
Federico Gagliardi ◽  
Daniele Bucci ◽  
...  

Annual accumulation of starch is affected by carbon reserves stored in the organs during the growing season and is controlled mainly by sink strength gradients within the tree. However, unfavorable environmental conditions (e.g., hail events) or application of management practices (e.g., defoliation to enhance overcolor in bicolor apple) could influence the allocation of storage carbohydrates. This preliminary research was conducted to determine the effects of early defoliation on the dry matter, starch, and soluble carbohydrate dynamics in woody organs, roots, and mixed buds classified by age and two levels of crop-load for one growing season in ‘Abbé Fétel’ pear trees (Oct. 2012 to mid-Jan. 2013 in the northern hemisphere). Regardless of the organs evaluated (woody organs, roots, and mixed buds), an increase of soluble carbohydrate concentration was observed in these organs in the period between after harvest (October) and January (dormancy period). Among all organs, woody short-old spurs showed the highest increase (+93.5%) in soluble sugars. With respect to starch, woody organs showed a clear trend of decreasing in concentration between October and January. In this case, short-old spurs showed the smallest decline in starch concentrations, only 6.5%, whereas in other tree organs starch decreased by 34.5%. After harvest (October), leaves showed substantially higher starch and soluble sugar concentrations in trees with lower crop-loads. These results confirm that in the period between October and January, dynamic interconversions between starch and soluble carbohydrates occur at varying magnitudes among organs in pear trees.


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