Variation in branch length in Fagopyrum esculentum in response to density and emergence date: No evidence for true plasticity

Botany ◽  
2009 ◽  
Vol 87 (9) ◽  
pp. 888-892 ◽  
Author(s):  
Wisdom Japhet ◽  
Daowei Zhou ◽  
Ping Wang

Plasticity is an important attribute that enables plants to maintain fitness in heterogeneous environments. The objective of this study was to investigate plasticity in branch length in Fagopyrum esculentum Moench. Seeds of the species were sown under two contrasting conditions through the manipulation of planting density (inter-planting distances at 20, 15, 10, and 5 cm) and sowing date (25 July, 1 August, 5 August, and 15 August). Allometric analysis of the relationships between branch length and total biomass showed a significant (p < 0.05) departure from isometry. This indicates that branch length increased linearly as a function of size. However, branch length was smaller in the group of plants sown at higher densities and at late sowing dates. True plasticity, which would have been indicated by significant differences in allometric exponents within treatments, was not observed in this study. Our results suggest that the differences observed in branch length were due to the direct effect of size rather than as a result of true plastic investment in branches.

1977 ◽  
Vol 57 (2) ◽  
pp. 317-321 ◽  
Author(s):  
G. H. GUBBELS

Two buckwheat (Fagopyrum esculentum Moench.) cultivars, Tokyo and Tempest, were grown in 1971, 1972 and 1973 at 8.5, 17, 34 and 68 kg/ha sowing rates and at early, mid- and late June sowing dates. Tempest lodged more than Tokyo, particularly in 1971. Yield generally declined with each delay in sowing. In 1971, yield increased with each increase in sowing rate, while in 1972 there was no difference due to rate. In 1973, yield increased to the third rate and levelled out to the fourth. Therefore, a sowing rate of over 34 kg/ha may be required to assure good yields each year. Seed weight tended to decrease with delay in sowing but was not affected by sowing rate.


2006 ◽  
Vol 84 (3) ◽  
pp. 485-492 ◽  
Author(s):  
Tianhui Wang ◽  
Daowei Zhou ◽  
Ping Wang ◽  
Hongxiang Zhang

Size-dependent reproductive effort is an important component of plant fitness. The responses of reproductive effort to environmental factors in Amaranthus retroflexus L. were measured in two experiments. A wide range of selection pressures were generated by manipulating the sowing date (29 April, 23 May, 18 June, and 14 July) and planting density (13.4, 36, 121, and 441 plants·m–2). Allometric analysis between reproductive biomass and vegetative biomass across treatments showed that reproductive effort increased with size in response to different planting densities but decreased with size in sowing dates experiment. The allometric exponent between treatments was not influenced by planting densities but had significant variation with sowing date. Total branch length could explain most of the variation of reproductive accumulation and allocation in planting density experiments. For the plants with different sowing dates, total branch length was the main determinant of reproductive biomass, while reproductive effort mainly depended on the number of primary branches per unit stem mass. Architectural constraints with size result in size-dependent reproduction. Size-dependent reproduction in A. retroflexus was influenced by available resources and environmental conditions through the mechanisms of self-regulation of architectural traits.


Author(s):  
М. С. Ульянченко

На фоні нестабільних погодних умов весняного періоду, що відмічаються останнім часом, встановлення оптимальних строків сівби районованих сортів гречки набуває актуального значення. У статті експериментальним шляхом вивчали шість сортів гречки (Fagopyrum esculentum Moench) вітчизняної селекції: Ярославна, Слобожанка, Руслана, Українка, Крупинка, СИН-3/02 залежно від строків сівби в умовах нестійкого зволоження центрального Лісостепу. Для проведення досліджень використовували загальноприйняті та спеціальні методики: продуктивність сортів гречки та аналіз зернового матеріалу за елементами продуктивності визначали після очищення зерна методом повітряної сепарації та перерахунку на стандартну 14 % вологість. Для умов 2015 року встановлено, що елементи продуктивності гречки (крупність та кількість зерен з рослини) мають суттєвий вплив на формування продуктивності культури. За масою 1000 зерен виокремилися сорт Крупинка за раннього строку сівби, суттєво менші значення отримали за цим показником у сортів Слобожанка та Українка, відповідно, за сівби в перший та другий строк. Усі інші сорти за крупністю зерна мали середнє значення. Строки сівби сорту СИН-3/02 не мали впливу на елементи продуктивності. В умовах 2016 року за крупністю зерна виокремилися сорти Ярославна, Руслана та Крупинка за раннього та середнього строків сівби. Всі сорти, що  вивчалися, забезпечили вищу крупність зерна за раннього строку сівби, за виключенням сортів Ярославна та Українка. За результатами дворічних досліджень визначено, що ранньостиглі сорти гречки Ярославна і Руслана доцільно висівати з середини першої декади травня. Сорти Слобожанка і Крупинка формують найбільшу продуктивність за сівби в перший та другий строк. Чіткого впливу терміну сівби на даний показник у сортів СИН-3/02 та Українка не виявлено. The set of optimal sowing dates of the buckwheat is to the actual value on the background of unstable weather of the springtime. In the article, six species of buckwheat (Fagopyrum esculentum Moench) of domestic breeding: Yaroslavna, Slobozhanka, Ruslana, Ukrainka, Krupynka, SIN-3/02 were studied experimentally, depending on the time of sowing in conditions of unstable moisture of the Central Forest-Steppe. For research, conventional methods and special methods were used: productivity of buckwheat varieties and analysis of grain material by the elements of productivity were determined after purification of the grain by air separation method and converted to a standard 14 % moisture content. For the 2015 conditions it has been established that the elements of the buckwheat productivity: the size and number of grains from the plant have a significant effect on the formation of the productivity of the crop. By weight of 1000 grains, Krupynka variety was distinguished at early term sowings; significant lower values ​​were obtained for this variety in Slobozhanka and Ukrainka, respectively for sowing in the first and second terms. All other varieties according to grain size had an average value. The lines of sowing of the variety SIN-3/02 did not influence the elements of productivity. In the conditions of 2016, the varieties Yaroslavna, Ruslana and Krupynka were distinguished by grain size for early and medium term sowing. All varieties put on the study ensured a higher grain size in early sowing, with the exception of Yaroslavna and Ukrainka varieties. According to the results of two-year studies, it has been determined that early varieties of buckwheat Yaroslavna and Ruslana should be sown from the middle of the first decade of May. Sloboda and Krupynka grades produce the highest seed yields in the first and second lines. The exact effect of the sowing date on this indicator in the varieties SIN-3/02 and Ukrainka was not detected.


Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 161
Author(s):  
Alberto A. Chassaigne-Ricciulli ◽  
Leopoldo E. Mendoza-Onofre ◽  
Leobigildo Córdova-Téllez ◽  
Aquiles Carballo-Carballo ◽  
Félix M. San Vicente-García ◽  
...  

Genotype, environmental temperature, and agronomic management of parents influence seed yield in three-way cross hybrid maize seed production. The objective of this research was to generate information on the seed production of six three-way cross hybrids and their progenitors, adapted to tropical lowlands. Data on days to—and duration of—flowering, distance to spike and stigmas, and seed yield of five female single crosses and five male inbred lines were recorded for different combinations of four planting densities and four sowing dates in Mexico. The effect of planting density was not significant. The male inbred line T10 was the earliest and highest seed yield and T31 the latest, occupying second place in yield. The single crosses T32/T10 and T13/T14 were the earliest and had the highest effective seed yield. At the earliest sowing date, the females were later in their flowering, accumulated fewer growing degree days (GDD), and obtained higher yields since the grain-filling period coincided with hot days and cool nights. To achieve greater floral synchronization and therefore greater production of hybrid seed, differential planting dates for parents are recommended based on information from the accumulated GDD of each parent. The three-way cross hybrids were classified according to the expected seed yield of the females and the complexity in the synchronization of flowering of their parents.


2021 ◽  
Vol 42 (3Supl1) ◽  
pp. 1529-1548
Author(s):  
Alberto Cargnelutti Filho ◽  
◽  
Rafael Vieira Pezzini ◽  
Ismael Mario Márcio Neu ◽  
Gabriel Elias Dumke ◽  
...  

The objective of this work was to model and identify the best models for estimating the leaf area, determined by digital photos, of buckwheat (Fagopyrum esculentum Moench) of the cultivars IPR91-Baili and IPR92-Altar, as a function of length (L), width (W) or length x width product (LW) of the leaf blade. Ten uniformity trials (blank experiments) were carried out, five with IPR91-Baili cultivar and five with IPR92-Altar cultivar. The trials were performed on five sowing dates. In each trial and cultivar, expanded leaves were collected at random from the lower, middle and upper segments of the plants, totaling 1,815 leaves. In these 1,815 leaves, L and W were measured and the LW of the leaf blade was calculated, which were used as independent variables in the model. The leaf area of each leaf was determined using the digital photo method (Y), which was used as a dependent variable of the model. For each sowing date, cultivar and thirds of the plant, 80% of the leaves (1,452 leaves) were randomly separated for the generation of the models and 20% of the leaves (363 leaves) for the validation of the models of leaf area estimation as a function of linear dimensions. For buckwheat, IPR91-Baili and IPR92-Altar cultivars, the quadratic model (Ŷ = 0.5217 + 0.6581LW + 0.0004LW2, R2 = 0.9590), power model (Ŷ = 0.6809LW1.0037, R2 = 0.9587), linear model (Ŷ = 0.0653 + 0.6892LW, R2 = 0.9587) and linear model without intercept (Ŷ = 0.6907LW, R2 = 0.9587) are indicated for the estimation of leaf area determined by digital photos (Y) based on the LW of the leaf blade (x), and, preferably, the linear model without intercept can be used, due to its greater simplicity.


2021 ◽  
Vol 42 (1) ◽  
pp. 105-122
Author(s):  
Alberto Cargnelutti Filho ◽  
◽  
Ismael Mario Márcio Neu ◽  
Rafael Vieira Pezzini ◽  
Gabriel Elias Dumke ◽  
...  

The aim of this study was to determine the rate of node appearance (RNA), the final number of nodes (FNN) and the period of node emission (PNE) in two buckwheat cultivars (Fagopyrum esculentum Moench) for different sowing dates, and to check variability in the RNA, FNN and PNE between the cultivars and sowing dates. The IPR91-Baili and IPR92-Altar cultivars were evaluated for 29 and 31 sowing dates from October to May in the 2017/2018 and 2018/2019 agricultural years respectively. In each experiment, a completely randomised design with five replications was used. The number of nodes (NN) on the main stem was counted twice a week in each plant (replication), from emission of the first node until the end of the cycle. The linear regression (y = a + bx) of the number of nodes (NN, y) was adjusted for each plant based on the number of days after emergence (DAE, x). The rate of node appearance (RNA), in days node-1, was determined from the inverse of the slope of the linear regression between NN and DAE (RNA = 1/b). The RNA was calculated for the period of node emission (PNE, in days), i.e. from emergence to emission of the last node. The final number of nodes (FNN) was counted at the end of node emission. Variability was found in the rate of node appearance (RNA), the final number of nodes (FNN) and the period of node emission (PNE) between the cultivars and sowing dates. The rate of node appearance ranges between 2.20 and 8.23 days node-1, the final number of nodes between 2.20 and 17.20, and the period of node emission between 16.60 and 49.20 days. Plants of the IPR91-Baili and IPR92-Altar cultivars show better vegetative development (lower RNA, higher FNN and greater PNE) when sown in November, December, January and February, compared to those sown in October, March, April and May.


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.


2015 ◽  
Vol 2 (1) ◽  
pp. 41-48
Author(s):  
Abrham Tezera Gessesse ◽  
Araya Alemie Berhe

One season experiment conducted at two sites in northern Ethiopia (Maychew and Mekelle). The objective of the research was to evaluate the effect of in-situ rainwater conservation and sowing-date on soil-water status, barley yield and infestation of weeds. The treatments include three alternative sowing-dates (ESD; NSD; and LSD) and two in-situ rainwater conservation measures (tie-ridge and soil-bund, replicated three times. Analysis of variance (ANOVA) was applied to evaluate the effect of the treatments on total biomass and rainwater use efficiency (RWUE) of the local barley. The average soil-water content in the upper 0.6 m root zone in the soil-bund and tie-ridge improved over the control treatment by 14% and 24%, respectively. The grain yield on tie-ridge was increased significantly compared to the control at Maychew site. Tie-ridge improved grain yield by 4% and 18% over the control at Mekelle and Maychew, respectively. NSD significantly improved the grain yield over LSD at both experimental sites. Neither of the sowing-dates nor the in-situ rainwater conservation measures had significantly increased the dry-matter of a barley crop. However, when NSD combined with tie-ridge, the grain yield was significantly improved compared to the LSD. There was no significant difference in weed infestation in both experimental sites due to applying in-situ rainwater conservation. But, numbers of weeds were significantly higher in ESD compared to NSD and LSD on both experimental sites. For this reason, NSD with tie-ridging technique can be used as an option to obtain higher barley grain yield.  


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