Calonectria theae. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
A. Peerally
Keyword(s):  
Geographical Distribution ◽  
Camellia Sinensis ◽  
Shade Tree ◽  
Mature Leaves ◽  
Young Leaves

Abstract A description is provided for Calonectria theae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Acacia spp., Albizia, Camellia sinensis, Eucalyptus spp. and Rhododendron (Azalea). DISEASE: Causes the well-known 'Cercosporella disease' of tea bushes. Spots on young leaves are at first brown or black and in humid weather enlarge and coalesce. On mature leaves spots are at first black then grey or greyish-white with a purplish margin. On fully mature leaves spots are brown or black then turn greyish. Tea bushes may be severely defoliated. Also causes root discoloration but not mortality of azaleas (52, 1935). GEOGRAPHICAL DISTRIBUTION: Ceylon and USA. Other records are of doubtful authenticity TRANSMISSION: By wind-borne conidia and ascospores in Ceylon. Transmission from Acacia decurrens, used as a shade tree, frequently reported.

Asperisporium caricae. [Descriptions of Fungi and Bacteria].

1972 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Experimental Work ◽  
West Indies ◽  
Carica Papaya ◽  
Black Spot ◽  
Seed Transmission ◽  
Leaf Fall ◽  
Mature Leaves ◽  
Early Suggestion ◽  
Young Leaves

Abstract A description is provided for Asperisporium caricae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Carica papaya. DISEASE: Black spot, blight or 'rust' of papaw (Carica papaya). Water-soaked spots on mature leaves become necrotic, usually circular and up to 4 mm diam., the dark conidia! masses being conspicuous on the under surface. Abundant spotting causes defoliation and over 50% leaf fall can occur. Similar spots form on the fruit; they cause shallow lesions and no decay. Young leaves are not attacked. GEOGRAPHICAL DISTRIBUTION: Restricted to Central and S. America, West Indies and USA (Florida, Texas) (CMI Map 488, ed. 1, 1972). TRANSMISSION: Presumably air dispersed but no experimental work has been reported and there is no confirmation of an early suggestion of seed transmission (4: 682).

Pestalotiopsis theae. [Descriptions of Fungi and Bacteria].

1971 ◽  
Author(s):  
J. E. M. Mordue
Keyword(s):  
Hong Kong ◽  
Sierra Leone ◽  
Papua New Guinea ◽  
Geographical Distribution ◽  
Camellia Sinensis ◽  
Canary Island ◽  
New Guinea ◽  
Young Leaves ◽  
Grey Blight

Abstract A description is provided for Pestalotiopsis theae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Camellia sinensis; also recorded on Cocos, Diospyros, Elaeis, Gossypium, Mangifera, Syzgium, Theobroma and a number of other unrelated hosts. DISEASE: Grey blight of tea, which begins as small brown spots on the leaves, later enlarging to 1 cm diam. or more and showing (on the upper surface) a greyish centre with light to dark brown margins. Lesions are usually circular or oval with concentric zonations marked out on the upper surface by the dark acervuli. On young leaves these zonations are often absent. Coalescence of the spots may occur. GEOGRAPHICAL DISTRIBUTION: Australia, Azores, Brazil, Burma, Ceylon, China, Canary Island, Ethiopia, Formosa, Ghana, Guinea, Hawaii, Hong Kong, India, Indonesia, Iran, Japan, Kenya, Laos, Malagasy Republic, Malawi, Malaysia, Mozambique, Nepal, Papua New Guinea, Peru, Rhodesia, Sierra Leone, Somaliland, S. Africa, Tanzania, Thailand, Turkey, Uganda, USSR, Vietnam (S.). TRANSMISSION: No detailed studies reported; the spores may be soil-borne (40: 184).

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.

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.

Phomopsis theae. [Distribution map].

1973 ◽  
Author(s):  
Keyword(s):  
Geographical Distribution ◽  
Camellia Sinensis ◽  
Distribution Map ◽  
New Distribution

Abstract A new distribution map is provided for Phomopsis theae Petch. Hosts: Tea (Camellia sinensis). Information is given on the geographical distribution in AFRICA, Kenya, Malawi, Tanzania, Uganda, ASIA, Ceylon, India.

Xanthomonas campestris pv. graminis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
K. E. Reay
Keyword(s):  
Geographical Distribution ◽  
Festuca Arundinacea ◽  
Xanthomonas Campestris ◽  
Natural Infection ◽  
Dactylis Glomerata ◽  
Phleum Pratense ◽  
Vascular Bundles ◽  
Poor Growth ◽  
Young Leaves ◽  
Natural Host Range

Abstract A description is provided for Xanthomonas campestris pv. graminis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Lolium italicum, L. multiflorum, L. perenne, Dactylis glomerata, Festuca pratensis, and Trisetum flavescens. Single cases of natural infection of Agropyron repens, Phalaris arundinacea and Phleum pratense are also recorded (62, 241), but their status in the natural host range is unknown. In inoculation tests (Egli et al., 1975; Egli & Schmidt, 1982) the following were highly susceptible: Alopecurus pratensis, Dactylis glomerata, Festuca arundinacea, F. pratensis, F. rubra, Lolium loliaceum, L. multiforum, L. parabolicae, L. perenne, L. remotum, L. temulentum, Phleum arenarium and P. bertolonii. Showing much less susceptibility were Agrostis alba, Arrhenatherum elatius, Phleum alpinum, P. phleoides, P. pratense, Poa annua, P. compressa, P. fertilis, P. memoralis, P. pratensis and P. trivialis. Leyns et al. (61, 6162) found that Agrosas tenuis and Festuca ovina were moderately susceptible when inoculated. Egli et al. (1975) recorded doubtful symptoms on Hordeum vulgare and Triacum aestivam on inoculation, but consider that they are unlikely to be naturally infected. DISEASE: Bacterial wilt of forage grasses. Symptoms usually first noticed at the heading stage, when young leaves curl and wither, and shoots remain stunted or may die. Other plants will continue to make poor growth and produce small, distorted inflorescences. Chlorotic and necrotic zones form on the older leaves along long stretches of vascular bundles, often extending into the sheaths. Bacterial streaming may be seen under the microscope from the cut ends of vascular bundles of infected tissue mounted in water. GEOGRAPHICAL DISTRIBUTION: CMI Map 533, ed. 1, 1979 lists France, Germany, Switzerland and Wales, to which must be added Scotland (63, 2925), Belgium (61, 4199), Netherlands, Norway (62, 241), and New Zealand (62, 241). Possibly in USA (IL; 61, 5045) though this disease is currently attributed to a Rickettsia- like organism. TRANSMISSION: Within the crop transmission is presumed to be by the blades of mowing machines.

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.

scholarly journals Antioxidant Activity Sonneratia caseolaris Leaves Extract at Different Maturity Stages

2020 ◽  
Vol 8 (3) ◽  
pp. 130
Author(s):  
Winarti Winarti ◽  
Boedi Setya Rahardja ◽  
Sudarno Sudarno
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Heart Attack ◽  
Total Content ◽  
Reactive Component ◽  
Mature Leaves ◽  
Maturity Stages ◽  
Sonneratia Caseolaris ◽  
Young Leaves ◽  
Ic50 Values

Free radical is a reactive component because it has one or more electrons. Free radical is very dangerous for our body because it can cause degenerative diseases, such as cancer, heart attack, and aging. Cancer and heart attack are one of the most killer disease. All we can do to decrease the free radical effect is consume antioxidant. S. caseolaris leaves has antioxidant activity, but it has known yet which stage of maturity is the best one for produce the highest antioxidant activity. This purpose of this research is knowing the influence between maturity and antioxidant activity at different maturity stages. This method of this research is experimental with Completely Randomized Design. The treatment in this research is vitamin C, fresh leaves in ethanol 96% extract, young leaves in ethanol 96% extract, and mature leaves in ethanol 96% extract. The main parameter of this research is IC50 values and the secondary parameters are total content of phytochemical in every extract. Data analysis using descriptive method with 4 treatments and five replications. The result of this research show that the maturity has influence in antioxidant activity. Inhibitory concentration 50 (IC50) values of shoot leaves extract, young leaves extract and mature leaves extract is 12.0013 ppm, 13.9915 ppm and 14.6613 ppm. All of them are called antioxidant which has very strong activities. The highest phytochemical compound is found on shoot leaves extract with ethanol 96% solvent.

scholarly journals Effect of kinetin on nucleic acid synthesis in senescing and young leaves in Brassica oleracea L. var. gongylodes L.

2015 ◽  
Vol 44 (4) ◽  
pp. 553-565
Author(s):  
J. Legocka ◽  
A. Szweykowska
Keyword(s):  
Molecular Weight ◽  
Nucleic Acid ◽  
Acid Synthesis ◽  
Inhibitory Effect ◽  
Rrna Synthesis ◽  
Low Molecular Weight ◽  
Chlorophyll B ◽  
Mature Leaves ◽  
Young Leaves ◽  
Brassica Oleracea L

In detached kohlrabi leaves senescing in the dark, the decrease in chlorophyll to was more pronounced than in chlorophyll a. The retardation by kinetin of the chlorophyll loss was also markedly stronger in the case of chlorophyll b. Using the fractionation of nucleic acids on polyacrylamide gels it has been shown that during leaf senescence the level of all RNA species decreased, whereas the amount of DNA was more or less constant. In the presence of kinetin, the loss of RNA was inhibited and the incorporation of precursor into the cytoplasmic rRNA as well as into low molecular weight RNA species was supported. Chloroplast rRNA synthesis has not been detected in mature leaves and kinetin showed no effect in this respect. In young expanding leaves detached and kept in light, the synthesis of cytoplasmic rRNA was strongly stimulated by kinetin, whereas in the case of Chloroplast rRNA only an inhibitory effect of kinetin could be found. The results suggest that the cytokinins are primarily involved in processes of the synthesis of cytoplasmic rRNA and low molecular RNA fractions, and in this way affect the development of plastids, in particular the course of their senescence.

scholarly journals Tolerance to water stress in boron-deficient tea (Camellia sinensis) plants

2012 ◽  
Vol 24 (1) ◽  
pp. 41-51 ◽  
Author(s):  
Roghieh Hajiboland ◽  
Soodabe Bastani
Keyword(s):  
Water Stress ◽  
Camellia Sinensis ◽  
Stress Conditions ◽  
Assimilation Rate ◽  
Antioxidant Defence System ◽  
Young Leaves ◽  
Net Assimilation ◽  
Single Stress ◽  
Tea Plants ◽  
Lower Ratio

Tolerance to water stress in boron-deficient tea (Camellia sinensis) plantsThe effects of boron (B) deficiency and water stress were studied in tea plants (Camellia sinensis[L.] O. Kuntze) grown in growth chambers in perlite irrigated with a nutrient solution. Dry matter production was reduced significantly by both low B supply and water stress. Shoot-root translocation of B declined in water-stressed plants. In addition, the re-translocation of B was impaired under drought, which was reflected in a significantly lower ratio of B content of young to old leaves in both B-deficient and B-sufficient plants. Leaf photochemical parameters were negatively influenced by B deficiency and water stress in the old but not in the young leaves. Although B-deficient plants were more conservative in relation to water loss following elevated stomatal limitation, their water potential was lower than in B-sufficient plants irrespective of the watering regime. Under the combined effects of B deficiency and water stress, the reduction in the CO2assimilation rate was more prominent than that under a single stress factor. The reduction of the net assimilation rate (A) in B-deficient plants due to water stress and in water-stressed plants due to low B supply were not accompanied by significant changes in the stomatal conductance, suggesting an involvement of non-stomatal factors. The activity of antioxidant enzymes and proline content increased under B deficiency and water stress conditions. Our results suggested that, in young leaves that have been developed under water stress, an acclimation to water stress conditions occurred that was well reflected in their more stable photochemistry, water relations and an efficient antioxidant defence system compared with the older leaves.

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