The effects of temperature and light energy on dry weight and leaf area changes in seedling plants of Lolium perenne L

1971 ◽  
Vol 22 (2) ◽  
pp. 177 ◽  
Author(s):  
JH Silsbury
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Lolium Perenne ◽  
Light Flux ◽  
Dry Weight ◽  
Light Energy ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Low Light ◽  
Net Assimilation

Nine identical seedling populations of Lolium perenne cv. Grasslands Ruanui were grown at different times in a controlled environment cabinet under 22, 38, and 117 watts m-2Visible radiation (16 hr day length) and at 10, 20, and 30�C for 32 days. The proportion of the total dry matter present as roots and that of the shoot dry weight present as leaf laminae were only slightly affected by the environment. Shoot growth was dominated by leaf growth; responses to the environment of the average relative growth rate (El,) and the average leaf area growth rate RA) were similar. RW and RA were maximal at 20�C at each light flux density and increased toward a maximum with increased radiation at each temperature. Maximum RW for seedling plants of L. perenne was about 25% per day. The net assimilation rate increased approximately linearly with increase in light flux and was scarcely affected by temperature. The leaf area ratio was greatly affected by changes in light energy, mainly owing to change in the specific leaf area. The rate of leaf appearance was accelerated by a temperature increase from 10 to 20�C. Total tiller number was maximal at 20�C and increased with light flux. When related to leaf number, tillering was reduced only by high temperature at low light energy. The relative changes in net assimilation rate induced by variation in light flux at 20�C were the same as those in the net photosynthesis of a single leaf lamina. The growth of seedling ryegrass plants in the field in winter is considered to be strongly dependent on temperature and much less restricted by low light energy.

scholarly journals Growth of canola hybrids resistant and sensitive to herbicides

2020 ◽  
Vol 41 (6supl2) ◽  
pp. 2911-2922
Author(s):  
Miria Rosa Durigon ◽  
◽  
Joanei Cechin ◽  
Franciele Mariani ◽  
Gerarda Beatriz da Silva Pinto ◽  
...  
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Dry Matter ◽  
Area Ratio ◽  
Leaf Area Ratio ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Absolute Growth Rate ◽  
Absolute Growth ◽  
Net Assimilation

Plant growth analysis is useful for determining adequate management practices and exploring the maximum yield potential of cultivars or hybrids. Canola hybrids with resistance to herbicides have been studied and registered for Brazilian conditions, as they improve weed management in canola crops. This study evaluated the growth of canola hybrids resistant to triazine or imidazolinone herbicides compared to a sensitive hybrid. The experiment was conducted using a completely randomized design, with four replications, in a bifactorial scheme using three hybrids and six sampling times. The canola hybrids used were Hyola 571CL (resistant to imidazolinones), Hyola 555TT (resistant to triazines), and Hyola 61 (sensitive to both herbicides). Height, leaf area, and dry matter of roots, leaves, stems, and shoots of the plants were evaluated at 14, 28, 42, 56, 70, and 119 days after emergence (DAE). The physiological indices absolute growth rate, leaf area ratio, specific leaf area, and net assimilation rate were calculated, and yield indices evaluated. Compared to Hyola 61, the Hyola 555TT hybrid showed lower values of leaf dry matter at 70 DAE, absolute growth rate up to 56 DAE, and net assimilation rate at 14 and 28 DAE, and a higher leaf area ratio at 56 DAE, whereas the hybrid Hyola 571CL presented lower leaf area and lower leaf dry matter at 70 DAE. At flowering, compared to Hyola 61, the hybrid Hyola 571CL presents lower leaf area, and the hybrids Hyola 555TT and Hyola 571CL have lower leaf dry matter accumulation. Differences in the growth of canola hybrids Hyola 555TT, Hyola 571CL and Hyola 61 do not cause differences in their grain yield.

scholarly journals COMPARISON OF GROWTH AND TUBER DEVELOPMENT IN THREE POTATO CULTIVARS WITH DIVERSE CANOPY SIZE

1977 ◽  
Vol 57 (3) ◽  
pp. 797-801 ◽  
Author(s):  
W. B. COLLINS
Keyword(s):  
Growth Rate ◽  
Potato Breeding ◽  
Dry Weight ◽  
Net Assimilation Rate ◽  
Tuber Growth ◽  
Assimilation Rate ◽  
Tuber Development ◽  
Final Yield ◽  
Net Assimilation ◽  
Canopy Size

The basis of differences in tuber and plant development in potato, due to differences in canopy size, was studied by measuring changes in plant dry weight and leaf area throughout the growing season. Differing canopy sizes were obtained by selecting three cultivars from the Canada Potato Breeding Program. These were F57048, Grand Falls, and F62008, which normally produce small, medium and large sized canopies respectively, with similar tuber yields. Differences in total and tuber dry weight through the season were slight compared to differences observed in leaf and stem growth. The branching capacity of the cultivars appeared to be the major determinant of canopy size. In these three cultivars, as canopy size increased, the initial tuber growth rate immediately following tuberization decreased. Thus, in the two smaller cultivars, the early tuber growth rate was more critical in determining final yield than was the case in the large-canopied cultivar, F62008. As expected, the net assimilation rate increased as canopy size decreased. The evidence indicated that the demands of the developing tubers exerted the greatest influence on the net assimilation rate.

scholarly journals Growth of marandu palisadegrass subjected to strategies of intermittent stocking

2009 ◽  
Vol 66 (6) ◽  
pp. 733-741 ◽  
Author(s):  
Alessandra Aparecida Giacomini ◽  
Sila Carneiro da Silva ◽  
Daniel Oliveira de Lucena Sarmento ◽  
Cauê Varesqui Zeferino ◽  
Salim Jacaúna Souza Júnior ◽  
...  
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Weight Ratio ◽  
Crop Growth ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Crop Growth Rate ◽  
Net Assimilation

Grazing strategies alter sward leaf area patterns of growth, affecting herbage accumulation and utilisation. The objective of this experiment was to evaluate the growth of marandu palisadegrass (Brachiaria brizantha cv. Marandu) swards subjected to strategies of intermittent stocking. The experiment was carried out in Piracicaba, São Paulo, Brazil, from October/2004 to September/2005. Swards were grazed at 95 and 100% canopy light interception (LI) to post-grazing heights of 10 and 15 cm, following a 2 × 2 factorial arrangement with four replications in a randomised complete block design. The response variables evaluated were: crop growth rate, relative growth rate, net assimilation rate, leaf area ratio and leaf weight ratio. In early and late spring, the highest crop growth rate was recorded for treatment 95/15 (11.2 and 10.1 g m-2 day-1, respectively), along with high values of net assimilation rate (4.4 and 6.9 g m-2 day-1, respectively), leaf area ratio (0.0095 and 0.0103 m-2 g-1, respectively) and leaf weight ratio (0.56 and 0.56 g g-1, respectively). To compensate reductions in net assimilation rate plants made some morphological and physiological adjustments increasing leaf area and leaf weight ratio. Relative growth rate and net assimilation rate were 26 and 50% higher, respectively, on swards grazed at 95% than at 100% LI. In early spring treatments 100/10 and 95/15 resulted in the highest relative growth rate (0.086 and 0.059 g m-2 day-1, respectively). Treatment 95/15 resulted in the most favourable pattern of growth (crop growth rate, relative growth rate, net assimilation rate), particularly during the transition period between winter and spring.

scholarly journals Seed Yield of Mungbean (Vigna radiata(L.) Wilczek) in relation to Growth and Developmental Aspects

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
M. M. A. Mondal ◽  
A. B. Puteh ◽  
M. A. Malek ◽  
M. R. Ismail ◽  
M. Y. Rafii ◽  
...  
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Growth Parameters ◽  
Net Assimilation Rate ◽  
Growth Stages ◽  
Flower Initiation ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Net Assimilation

Growth parameters such as leaf area (LA), total dry mass (TDM) production, crop growth rate (CGR), relative growth rate (RGR), and net assimilation rate (NAR) were compared in six varieties of mungbean under subtropical condition (24°8′ N 90°0′ E) to identify limiting growth characters for the efficient application of physiology breeding for higher yields. Results revealed that a relatively smaller portion of TDM was produced before flower initiation and the bulk of it after anthesis. The maximum CGR was observed during pod filling stage in all the varieties due to maximum leaf area (LA) development at this stage. Two plant characters such as LA and CGR contributed to the higher TDM production. Results indicated that high yielding mungbean varieties should possess larger LA, higher TDM production ability, superior CGR at all growth stages, and high relative growth rate and net assimilation rate at vegetative stage which would result in superior yield components.

Productivity of the Oil Palm (Elaeis guineensis Jacq.) in Malaysia

1971 ◽  
Vol 7 (2) ◽  
pp. 129-136 ◽  
Author(s):  
R. H. V. Corley ◽  
B. S. Gray ◽  
Ng Siew Kee
Keyword(s):  
Growth Rate ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Elaeis Guineensis ◽  
Crop Growth ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Area Index ◽  
Crop Growth Rate ◽  
Net Assimilation

SUMMARYCrop Growth Rate, Leaf Area Index, Net Assimilation Rate and Harvest Index were estimated for oil palms in nine age groups growing on coastal alluvial soils in Malaysia. The mean Crop Growth Rate of mature palms was 29·83 t./ha./yr, with a Leaf Area Index of 3·61, and Net Assimilation Rate was 0·16 gm./dm.2/wk. Photosynthetic efficiency was about 2·2 per cent. Oil constituted about 17 per cent of total dry matter production. Possibilities for improving the yield of oil are briefly discussed.

scholarly journals Influence of Rootstock, Scion, and Water Deficits on Growth of `Colt' and `Meteor' Cherry Trees

HortScience ◽  
1991 ◽  
Vol 26 (9) ◽  
pp. 1204-1207 ◽  
Author(s):  
Thomas G. Ranney ◽  
Nina L. Bassuk ◽  
Thomas H. Whitlow
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Prunus Avium ◽  
Dry Weight ◽  
Root Surface ◽  
Prunus Cerasus ◽  
Root Surface Area ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Net Assimilation

Growth and physiological characteristics were evaluated in autografted and reciprocally grafted plants of Prunus avium L. ×pseudocerasus Lindl. `Colt' and Prunus cerasus L. `Meteor'. Containerized plants were grown for 150 days in a greenhouse under either well-watered or water-stressed conditions. Both the scion and rootstock influenced growth (relative growth rate, R̄), morphological [leaf area : root surface area (LARSA) and specific leaf area (SLA)], and physiological (mean net assimilation rate, Ē) characteristics of grafted plants. Regardless of the watering regime, plants with `Meteor' scions and `Colt' rootstocks maintained higher R̄ than plants with `Colt' scions and `Meteor' rootstocks. This enhanced growth occurred as a result of higher Ē. Measurements on water-stressed plants also showed that the graft combination of `Meteor' on `Colt' had the lowest LARSA, while the reciprocal combination of `Colt' on `Meteor' had the highest. Differences in LARSA among water-stressed plants primarily reflected changes in SLA, as influenced by both rootstock and scion, and not in partitioning of dry weight between these organs.

Comparative analysis of 1st-year growth in six deciduous tree species

1980 ◽  
Vol 10 (1) ◽  
pp. 35-41 ◽  
Author(s):  
R. E. Farmer Jr.
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Relative Growth Rate ◽  
Tree Species ◽  
Net Assimilation Rate ◽  
Deciduous Tree ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Quercus Species ◽  
Net Assimilation

Classical growth analysis was used to examine the basis of major variation in seedling growth characteristics among and within six deciduous tree species in nursery beds. A combination of high investment in leaf area and substantial net assimilation rate accounted for the high relative growth rate of Liriodendrontulipifera L. and Prunusserotina Ehrh.; these species also produced the largest seedlings in the test. Final weight of four Quercus species was closely associated with initial leaf area established at germination; Q. rubra L. and Q. prinus L. had the largest seedlings despite having net assimilation rates lower than Q. alba L. and Q. ilicifolia Wangenh., the smallest seedlings in the test. Within species, relative growth rate was significantly correlated with both net assimilation rate and relative growth rate of leaf area. Leaf area partition coefficient was positively correlated with relative growth rate in L. tulipifera, P. serotina, and Q. rubra but not in Q. alba, Q. prinus, and Q. ilicifolia.

Sign in / Sign up

Export Citation Format

Share Document