scholarly journals Further Studies on the Role of Leaves in Sugarcane Flowering

1969 ◽  
Vol 58 (4) ◽  
pp. 393-405
Author(s):  
Teh-ling Chu ◽  
J. L. Serapión
Keyword(s):  
Flowering Time ◽  
Flowering Response ◽  
Sugarcane Varieties ◽  
Floral Stimulus ◽  
Mature Leaves ◽  
Defoliation Treatment ◽  
Young Leaves ◽  
Flowering Intensity

The role played by leaves in the perception and inhibition of the flowering stimulus was studied through defoliation treatment in three sugarcane varieties. It was found that the expanding leaves (0 and —1) in the variety P.R. 980 appear to be most effective in producing a flowering stimulus. The mature leaves (+3 and +4) in the variety Cl 41-223 appear to produce a transmissible flowering inhibitor. Absence of the young leaves within the leaf spindle during a period critical to initiation of inflorescence primordia resulted in a significant reduction of flowering intensity in varieties N.Co. 310 and Cl 41-223, and a marked delay in the flowering time in N.Co. 310. Removal of these leaves during subsequent stages of inflorescence caused a somewhat depressive flowering response and a considerable delay in the flowering time of N.Co. 310. A late-initiating variety, Cl 41-223 appears to begin producing a floral stimulus around August 20, about 2 to 3 weeks later than that of the early-initiating variety N.Co. 310.

scholarly journals The role of JrPPOs in the browning of walnut explants

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shugang Zhao ◽  
Hongxia Wang ◽  
Kai Liu ◽  
Linqing Li ◽  
Jinbing Yang ◽  
...  
Keyword(s):  
Tissue Culture ◽  
Production Efficiency ◽  
Phenolic Content ◽  
Leaf Tissue ◽  
Limiting Factor ◽  
Mature Leaves ◽  
Survival Percentage ◽  
Highly Active ◽  
Young Leaves

Abstract Background Tissue culture is an effective method for the rapid breeding of seedlings and improving production efficiency, but explant browning is a key limiting factor of walnut tissue culture. Specifically, the polymerization of PPO-derived quinones that cause explant browning of walnut is not well understood. This study investigated explants of ‘Zanmei’ walnut shoot apices cultured in agar (A) or vermiculite (V) media, and the survival percentage, changes in phenolic content, POD and PPO activity, and JrPPO expression in explants were studied to determine the role of PPO in the browning of walnut explants. Results The results showed that the V media greatly reduced the death rate of explants, and 89.9 and 38.7% of the explants cultured in V media and A media survived, respectively. Compared with that of explants at 0 h, the PPO of explants cultured in A was highly active throughout the culture, but activity in those cultured in V remained low. The phenolic level of explants cultured in A increased significantly at 72 h but subsequently declined, and the content in the explants cultured in V increased to a high level only at 144 h. The POD in explants cultured in V showed high activity that did not cause browning. Gene expression assays showed that the expression of JrPPO1 was downregulated in explants cultured in both A and V. However, the expression of JrPPO2 was upregulated in explants cultured in A throughout the culture and upregulated in V at 144 h. JrPPO expression analyses in different tissues showed that JrPPO1 was highly expressed in stems, young leaves, mature leaves, catkins, pistils, and hulls, and JrPPO2 was highly expressed in mature leaves and pistils. Moreover, browning assays showed that both explants in A and leaf tissue exhibited high JrPPO2 activity. Conclusion The rapid increase in phenolic content caused the browning and death of explants. V media delayed the rapid accumulation of phenolic compounds in walnut explants in the short term, which significantly decreased explants mortality. The results suggest that JrPPO2 plays a key role in the oxidation of phenols in explants after branch injury.

scholarly journals Isotopic signatures reveal zinc cycling in the natural habitat of hyperaccumulator Dichapetalum gelonioides subspecies from Malaysian Borneo

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Antony van der Ent ◽  
Philip Nti Nkrumah ◽  
Mark G. M. Aarts ◽  
Alan J. M. Baker ◽  
Fien Degryse ◽  
...  
Keyword(s):  
Leaf Litter ◽  
Natural Habitat ◽  
Parent Rock ◽  
Deep Soil ◽  
Isotopic Signatures ◽  
Mature Leaves ◽  
Young Leaves ◽  
Malaysian Borneo ◽  
Zn Isotopes

Abstract Background Some subspecies of Dichapetalum gelonioides are the only tropical woody zinc (Zn)-hyperaccumulator plants described so far and the first Zn hyperaccumulators identified to occur exclusively on non-Zn enriched 'normal' soils. The aim of this study was to investigate Zn cycling in the parent rock-soil-plant interface in the native habitats of hyperaccumulating Dichapetalum gelonioides subspecies (subsp. pilosum and subsp. sumatranum). We measured the Zn isotope ratios (δ66Zn) of Dichapetalum plant material, and associated soil and parent rock materials collected from Sabah (Malaysian Borneo). Results We found enrichment in heavy Zn isotopes in the topsoil (δ66Zn 0.13 ‰) relative to deep soil (δ66Zn -0.15 ‰) and bedrock (δ66Zn -0.90 ‰). This finding suggests that both weathering and organic matter influenced the Zn isotope pattern in the soil-plant system, with leaf litter cycling contributing significantly to enriched heavier Zn in topsoil. Within the plant, the roots were enriched in heavy Zn isotopes (δ66Zn ~ 0.60 ‰) compared to mature leaves (δ66Zn ~ 0.30 ‰), which suggests highly expressed membrane transporters in these Dichapetalum subspecies preferentially transporting lighter Zn isotopes during root-to-shoot translocation. The shoots, mature leaves and phloem tissues were enriched in heavy Zn isotopes (δ66Zn 0.34–0.70 ‰) relative to young leaves (δ66Zn 0.25 ‰). Thisindicates that phloem sources are enriched in heavy Zn isotopes relative to phloem sinks, likely because of apoplastic retention and compartmentalization in the Dichapetalum subspecies. Conclusions The findings of this study reveal Zn cycling in the rock-soil-plant continuum within the natural habitat of Zn hyperaccumulating subspecies of Dichapetalum gelonioides from Malaysian Borneo. This study broadens our understanding of the role of a tropical woody Zn hyperaccumulator plant in local Zn cycling, and highlights the important role of leaf litter recycling in the topsoil Zn budget. Within the plant, phloem plays key role in Zn accumulation and redistribution during growth and development. This study provides an improved understanding of the fate and behaviour of Zn in hyperaccumulator soil-plant systems, and these insights may be applied in the biofortification of crops with Zn.

Sorbitol Versus Sucrose as Photosynthesis and Translocation Products in Developing Apricot Leaves

1985 ◽  
Vol 12 (6) ◽  
pp. 657 ◽  
Author(s):  
RL Bieleski ◽  
RJ Redgwell
Keyword(s):  
Leaf Development ◽  
Main Product ◽  
Mature Leaf ◽  
Young Leaf ◽  
Mature Leaves ◽  
Specific Transport ◽  
Young Leaves

Very young apricot leaves behave like the young leaves of most plants; that is, [14C]sucrose is formed as the main product of 14CO2 photosynthesis, and also when the leaves are supplied with [14C]glucose. [14C]sorbitol is not produced, and is poorly metabolized when fed to the leaf. Expanding leaves behave differently: [14C]sorbitol and [14C]sucrose are formed in similar amounts from both 14CO2 and [14C]glucose; and when [14C]sorbitol is supplied, it is readily metabolized and utilized for growth. Mature leaves are different again. They form [14C]sorbitol as the main product from 14CO2 and from [14C]glucose, and they do not metabolize [14C]sorbitol at all. Thus during development, apricot leaves gain but then lose the ability to utilize sorbitol. They also gain and keep the ability to synthesize sorbitol. This suggests that different biochemical paths exist for sorbitol formation and utilization, and that these paths are differently developed in the various stages of leaf development. Although the very young leaves did not synthesize sorbitol from CO2 or glucose, they contained it as their major sugar. Translocation behaviour was therefore studied. Neither the very young leaves nor the expanding leaves export any photosynthate, but the mature leaf rapidly translocates carbohydrate, mainly in the form of sorbitol, to the younger leaves as well as the rest of the plant. [14C]sorbitol supplied to the mature leaf can be recovered in that form from the very young leaf on the same shoot. This further establishes the role of sorbitol in apricot as a specific transport carbohydrate.

scholarly journals The Role of Leaves and Carbohydrates in Flowering of Protea cv. Lady Di

HortScience ◽  
2001 ◽  
Vol 36 (5) ◽  
pp. 905-908
Author(s):  
Audrey I. Gerber ◽  
Karen I. Theron ◽  
Gerard Jacobs
Keyword(s):  
Flowering Time ◽  
Growth And Development ◽  
Dry Weight ◽  
Early Growth ◽  
Major Portion ◽  
Inflorescence Development ◽  
Mature Leaves ◽  
Early Stages

Inflorescence initiation in Protea cv. Lady Di (P. magnifica Link × P. compacta R. Br.) occurs predominantly on the spring growth flush when it is subtended by one or more previous growth flushes. Mature, over-wintering leaves are essential for induction of flowering in `Lady Di', and are also crucial to the early stages of inflorescence initiation and differentiation. Defoliation before elongation of the spring growth flush was complete prevented flowering, and shoots either remained vegetative or produced inflorescences that aborted. Levels of carbohydrates in the stem and leaves of overwintering shoots were low, and early growth and development of both the spring flush and inflorescence were, therefore, supported by current photosynthates from the mature leaves on the overwintering shoot. Likewise, reserve carbohydrates available in the flowering shoot were insufficient to account for the rapid increase in dry weight during the major portion of growth of the spring flush and inflorescence. This increase occurred after elongation of the spring flush was complete and was supported by current photosynthates from the leaves of the spring flush. Defoliation treatments that did not prevent inflorescence initiation had no effect on inflorescence development or on flowering time.

Review on Ethnobotany and Phytopharmacology on Mesua ferrea Linn

2021 ◽  
pp. 195-199
Author(s):  
Sruthikrishna P.K.
Keyword(s):  
Health Issues ◽  
Phytochemical Screening ◽  
Asian Countries ◽  
Mature Leaves ◽  
Young Leaves ◽  
Tropical Areas ◽  
Anti Oxidant ◽  
Dark Green ◽  
Almost All

This work was performed to study the ethnobotany and phytopharmacological properties of M. ferrea L. It is widely distributed in the tropical areas of the world, especially in the Asian countries and is traditionally used by the local peoples for curing diseases ranging from head ache to cancer. Mesua ferrea is cultivated as an ornamental plant and young leaves are reddish yellow in color while mature leaves are blue grey to dark green in appearance with fragrant white flowers. This study reveals that almost all part of the plant have high medicinal property against different ailments. M. ferrea Linn being used for its anticancer, antineoplastic, disinfectant, anti oxidant, hepato-protective, anti arthritic, diuretic, analgesic etc. properties. The phytochemical screening confirms the presence of phenyl coumarins, xanthones, triterpenoids, tannin and saponin as main constituents responsible for its biological activity. It is also used in the cosmetics. This can be used as remedial agents for various health issues. This review reveals the phyto-pharmacological role of this medicinal plant.

Karakter Morfologi Daun Ubi Jalar Sebagai Bahan Pangan Suku Dani Distrik Kurulu Jayawijaya

Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Antonius Suparno ◽  
Opalina Logo ◽  
Dwiana Wasgito Purnomo
Keyword(s):  
Sweet Potato ◽  
Leaf Morphology ◽  
Food Source ◽  
Staple Food ◽  
Sweet Potatoes ◽  
General Outline ◽  
Leaf Vein ◽  
Mature Leaves ◽  
Young Leaves ◽  
Tuber Roots

Sweet potato serves as a staple food for people in Jayawijaya. Many cultivars of sweet potatoes have been cultivated by Dani tribe in Kurulu as foot for their infant, child and adult as well as feeding especially for pigs. Base on the used of sweet potatoes as food source for infant and child, this study explored 10 different cultivars. As for the leaf morphology, it was indentified that the mature leaves have size around 15 � 18 cm. general outline of the leaf is reniform (40%), 60% have green colour leaf, 50% without leaf lobe, 60% of leaf lobes number is one, 70% of shape of central leaf lobe is toothed. Abazial leaf vein pigmentation have purple (40%), and petiole pigmentation is purple with green near leaf (60%), besides its tuber roots, sweet potatoes are also harvested for its shoots and green young leaves for vegetables.

Variation in the morphology and flowering time of cluster clover (Trifolium glomeratum L.) and its relationship to distribution in southern Australia

1995 ◽  
Vol 46 (5) ◽  
pp. 1027 ◽  
Author(s):  
FP Smith ◽  
PS Cocks ◽  
MA Ewing
Keyword(s):  
Genetic Variation ◽  
Flowering Time ◽  
Seed Mass ◽  
Annual Rainfall ◽  
Strongly Correlated ◽  
Summer Maximum ◽  
Maximum Temperatures ◽  
Pattern Of Variation ◽  
Growth Habits

Cluster clover is a widely distributed and ecologically successful introduced legume in southern Australia. In an attempt to understand the role of genetic variation in this success, morphological and physiological traits were measured in 94 accessions from southern Australia and 6 from the Mediterranean basin. Flowering time ranged from 105 to 185 days after sowing, but was not strongly correlated with annual rainfall or length of growing season at the site of collection. Variation in other traits partitioned the populations into two morphs which, apart from flowering time and leaf marker, were largely homogeneous. The morphs differed significantly in floret number per inflorescence (22 v. 32-37) and seed mass (379 8g v. 523 8g), had different growth habits and strong within-morph associations between leaf markers and stipule and petal coloration. The morphs differed in their distributions within southern Australia and the pattern of distribution was related to summer maximum temperatures, winter minimum temperatures and spring rainfall. These results demonstrate that genetic variation has been important to the success of cluster clover and suggests that the variation is organized. The pattern of variation observed and its relationship to ecogeography is consistent with findings for other highly inbreeding species. A map of the species distribution in Western Australia is presented.

Studies on the flowering biology of red sorrel (Rumex acetosella) ramets from lowbush blueberry (Vaccinium angustifolium) fields in Nova Scotia, Canada

Botany ◽  
2015 ◽  
Vol 93 (1) ◽  
pp. 41-46 ◽  
Author(s):  
Scott N. White ◽  
Nathan S. Boyd ◽  
Rene C. Van Acker ◽  
Clarence J. Swanton
Keyword(s):  
Nova Scotia ◽  
Combined Effects ◽  
Perennial Species ◽  
Weed Species ◽  
Vaccinium Angustifolium ◽  
Perennial Weed ◽  
Flowering Response ◽  
Lowbush Blueberry ◽  
Rumex Acetosella

Red sorrel (Rumex acetosella L.) is a ramet-producing herbaceous creeping perennial species commonly found as a weed in commercially managed lowbush blueberry (Vaccinium angustifolium Aiton) fields in Nova Scotia, Canada. Flowering and seed production occur primarily in overwintering ramets of this species, indicating a potential vernalization requirement for flowering. This study was therefore initiated to examine the role of vernalization, photoperiod, and pre-vernalization stimulus on ramet flowering. Red sorrel ramets propagated from creeping roots and seeds collected from established red sorrel populations in lowbush blueberry had an obligate requirement for vernalization to flower. Ramet populations maintained under pre- and post-vernalization photoperiods of 16 h flowered following 12 weeks of vernalization at 4 ± 0.1 °C, whereas those maintained under constant 16, 14, or 8 h photoperiods without vernalization did not flower. Vernalization for 10 weeks maximized, but did not saturate, the flowering response. Pre-vernalization photoperiod affected flowering response, with increased flowering frequency observed in ramet populations exposed to decreasing, rather than constant, photoperiod prior to vernalization. This study represents the first attempt to determine the combined effects of vernalization and photoperiod on red sorrel flowering, and the results provide a benchmark for the future study of flowering and sexual reproduction in this economically important perennial weed species.

scholarly journals Meteorological conditions, ozone concentration and leaf age affect gas exchange in Psidium guajava ‛Palumaʼ

Hoehnea ◽  
2017 ◽  
Vol 44 (2) ◽  
pp. 236-245 ◽  
Author(s):  
Juliana Moreno Pina ◽  
Sérgio Tadeu Meirelles ◽  
Regina Maria de Moraes
Keyword(s):  
Gas Exchange ◽  
Ozone Concentration ◽  
Leaf Age ◽  
Psidium Guajava ◽  
Meteorological Conditions ◽  
Gas Exchanges ◽  
Mature Leaves ◽  
Young Leaves ◽  
Entire Experiment ◽  
The City

ABSTRACT This study aimed to investigate the importance of leaf age, meteorological conditions and ozone concentration (O3) on gas exchange of Psidium guajava ‛Paluma'. Saplings were grown and exposed in standard conditions in the city of São Paulo, in six periods of three months with weekly measurements in young and mature leaves. Gas exchanges were higher in young leaves for almost the entire experiment. Mature leaves showed greater reduction in gas exchange. The multivariate analysis of biotic and abiotic variables indicated that vapor pressure deficit (VPD), O3 concentration and radiation were the main variables associated with gas exchange decrease in young leaves. In mature leaves the influence of VPD is lower, but the temperature importance is higher. Moreover, the opposition between assimilation and O3 is more evident in mature leaves, indicating their greater sensitivity to O3.

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