GROWTH AND DEVELOPMENT OF THE LOWBUSH BLUEBERRY: APICAL ABORTION

1963 ◽  
Vol 41 (9) ◽  
pp. 1319-1324 ◽  
Author(s):  
W. G. Barker ◽  
W. B. Collins
Keyword(s):  
Vegetative Growth ◽  
Growth And Development ◽  
Apical Meristem ◽  
Shoot Growth ◽  
Strong Indication ◽  
Vegetative Tissue ◽  
Aerial Shoot ◽  
Lowbush Blueberry ◽  
Below Ground ◽  
High Level

The semicultivated lowbush blueberry is fire-pruned on a 3- to 4-year cycle. In spring, vegetative growth is accomplished through the development of an axillary bud on an aerial shoot. In a fire-pruned area, the growth is delayed in both its initiation and termination by as much as a month and arises either from axillary buds on the unburned below-ground portions of the aerial stems, or from rhizome seated buds. Shoot growth is terminated by the abortion of the apical meristem and the death of the proximal portions of the axis. Evidence is presented suggesting that the death of the apex is not triggered by an appropriate photoperiod. Further, although it is inherently controlled, it does not follow the production of a specified quantity (relative to clone) of leaf nor vegetative tissue and is not related to the development of a specified (per clone) leaf photosynthetic area. Finally, there is a strong indication that the death of the shoot is speeded by the presence of a high level of auxin.

Effects of fruiting on vegetative growth and development dynamics of grapevines (Vitis vinifera cv. Semillon) can be traced back to events at or before budbreak

2010 ◽  
Vol 37 (8) ◽  
pp. 756 ◽  
Author(s):  
Dennis H. Greer ◽  
Chris Weston
Keyword(s):  
Vitis Vinifera ◽  
Vegetative Growth ◽  
Growth And Development ◽  
Shoot Growth ◽  
Leaf Primordia ◽  
Vitis Vinifera L ◽  
Development Patterns ◽  
Maximum Expansion ◽  
Constant Rate ◽  
The Impact

Leaf and shoot growth and development patterns in Vitis vinifera L. cv. Semillon were analysed dynamically. Potted fruiting and vegetative vines were grown in controlled conditions and budbreak, leaf and internode (metamers) appearance and expansion were measured. Buds were also dissected microscopically. Metamer appearance occurred in three zones; the first 5–6 metamers emerged as a cluster with fastest expansion and largest size. Marked differences in sizes and dynamics of growth occurred between fruiting and vegetative vines because flowers were absent. The next 13–14 preformed metamers appeared at a constant rate and metamer size declined along the shoot. Timing of maximum expansion and duration of growth of the metamers in this cohort was increasingly delayed in fruiting compared with vegetative vines. Beyond node 20, neoformed metamers emerged at a slow constant rate and were smallest overall. Throughout development, extension of the internode occurred before expansion of the subtending leaf, consistent with the liana habit of grapevines. Differences between fruiting and vegetative vines in metamer development were observed just after budbreak and these differences generally appreciated over time. The impact of reproduction on vegetative growth can, therefore, likely be attributed to competition for carbohydrate between floral and leaf primordia in the dormant or breaking bud, accounting for the smaller leaves and internodes.

scholarly journals The HK5 and HK6 cytokinin receptors mediate diverse developmental pathways in rice

Development ◽  
2020 ◽  
Vol 147 (20) ◽  
pp. dev191734
Author(s):  
Christian A. Burr ◽  
Jinjing Sun ◽  
Maria V. Yamburenko ◽  
Andrew Willoughby ◽  
Charles Hodgens ◽  
...  
Keyword(s):  
Growth And Development ◽  
Apical Meristem ◽  
Shoot Growth ◽  
Floral Development ◽  
Developmental Pathways ◽  
Cytokinin Signaling ◽  
Cytokinin Receptors ◽  
Root And Shoot Growth ◽  
Cytokinin Response

ABSTRACTThe phytohormone cytokinin regulates diverse aspects of plant growth and development. Our understanding of the metabolism and perception of cytokinin has made great strides in recent years, mostly from studies of the model dicot Arabidopsis. Here, we employed a CRISPR/Cas9-based approach to disrupt a subset of cytokinin histidine kinase (HK) receptors in rice (Oryza sativa) in order to explore the role of cytokinin in a monocot species. In hk5 and hk6 single mutants, the root growth, leaf width, inflorescence architecture and/or floral development were affected. The double hk5 hk6 mutant showed more substantial defects, including severely reduced root and shoot growth, a smaller shoot apical meristem, and an enlarged root cap. Flowering was delayed in the hk5 hk6 mutant and the panicle was significantly reduced in size and infertile due to multiple defects in floral development. The hk5 hk6 mutant also exhibited a severely reduced cytokinin response, consistent with the developmental phenotypes arising from a defect in cytokinin signaling. These results indicate that HK5 and HK6 act as cytokinin receptors, with overlapping functions to regulate diverse aspects of rice growth and development.

SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

1995 ◽  
Vol 53 ◽  
pp. 978-979
Author(s):  
G. M. Hutchins ◽  
J. S. Gardner
Keyword(s):  
Growth And Development ◽  
Furfuryl Alcohol ◽  
Apical Meristem ◽  
Plant Cells ◽  
Triticum Aestivum L ◽  
Morphological Development ◽  
Naturally Occurring ◽  
Chinese Spring Wheat ◽  
Sem Study ◽  
Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

scholarly journals Effects of Shading on Carbohydrates of Syzygium samarangense

2019 ◽  
Vol 47 (4) ◽  
pp. 1252-1257
Author(s):  
Ying JIAN ◽  
Guolin WU ◽  
Donghui ZHOU ◽  
Zhiqun HU ◽  
Zhenxuan QUAN ◽  
...  
Keyword(s):  
Vegetative Growth ◽  
Shoot Growth ◽  
Soluble Sugar ◽  
Apple Fruit ◽  
Digital Object Identifier ◽  
Digital Object ◽  
Carbohydrate Accumulation ◽  
Tropical Fruit ◽  
Total Soluble Sugar ◽  
Carbohydrate Levels

Wax apple (Syzygium samarangense) is an important tropical fruit tree cultivated in Southeast Asian. It produces red pear-like shape fruits. The fruit flesh is considered high in antioxidants, phenolics, and flavonoids that have a potential to contribute to the human healthy diet, and was proved to have anti-inflammatory and antimicrobial characteristics. To allow year-round marketing of high quality wax apple fruit, growers always perform shading to inhibit new flushes so as to repress vegetative growth and promote reproductive growth. To investigate the effect of shading on carbohydrates, wax apple trees were shaded with sun shade nets under field conditions. The effects of shading on shoot growth were studied and leaf carbohydrate levels of the trees were determined. The results showed that shading inhibit the the growth of the terminal shoots and promoted bud dormancy. Shading also reduced total soluble sugar, sucrose, glucose, fructose, and starch levels of leaves. The results suggested that shading reduced carbohydrate accumulation and repressed vegetative growth.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Further Studies on Coenurus glomeratus

1940 ◽  
Vol 18 (2-3) ◽  
pp. 95-102 ◽  
Author(s):  
Phyllis A. Clapham
Keyword(s):  
Old Age ◽  
Vegetative Growth ◽  
Growth And Development ◽  
Small Area ◽  
Cyst Formation ◽  
Daughter Cyst ◽  
New Hosts ◽  
Growth And Reproduction

The structure of the normal coenurus of M. glomeratus is described and some observations have been made on its powers of budding and vegetative growth and reproduction. It is suggested that only a small area of the cyst has the power of growth and development and that budding and daughter cyst formation is an action which attempts to stave off old age and sterility. It has been found possible to cause new growths and infections by the transplantation of certain elements to new hosts. Some remarks are made on the occurrence of abnormalities in a coenurus cyst.

scholarly journals Analysis of the Bacillus subtilis spoIIIJ Gene and Its Paralogue Gene, yqjG

2002 ◽  
Vol 184 (7) ◽  
pp. 1998-2004 ◽  
Author(s):  
Takako Murakami ◽  
Koki Haga ◽  
Michio Takeuchi ◽  
Tsutomu Sato
Keyword(s):  
Bacillus Subtilis ◽  
Membrane Proteins ◽  
Vegetative Growth ◽  
Fluorescent Protein ◽  
Specific Expression ◽  
Rich Media ◽  
Green Fluorescent ◽  
High Level ◽  
Fluorescent Protein Reporter

ABSTRACT The Bacillus subtilis spoIIIJ gene, which has been proven to be vegetatively expressed, has also been implicated as a sporulation gene. Recent genome sequencing information in many organisms reveals that spoIIIJ and its paralogous gene, yqjG, are conserved from prokaryotes to humans. A homologue of SpoIIIJ/YqjG, the Escherichia coli YidC is involved in the insertion of membrane proteins into the lipid bilayer. On the basis of this similarity, it was proposed that the two homologues act as translocase for the membrane proteins. We studied the requirements for spoIIIJ and yqjG during vegetative growth and sporulation. In rich media, the growth of spoIIIJ and yqjG single mutants were the same as that of the wild type, whereas spoIIIJ yqjG double inactivation was lethal, indicating that together these B. subtilis translocase homologues play an important role in maintaining the viability of the cell. This result also suggests that SpoIIIJ and YqjG probably control significantly overlapping functions during vegetative growth. spoIIIJ mutations have already been established to block sporulation at stage III. In contrast, disruption of yqjG did not interfere with sporulation. We further show that high level expression of spoIIIJ during vegetative phase is dispensable for spore formation, but the sporulation-specific expression of spoIIIJ is necessary for efficient sporulation even at the basal level. Using green fluorescent protein reporter to monitor SpoIIIJ and YqjG localization, we found that the proteins localize at the cell membrane in vegetative cells and at the polar and engulfment septa in sporulating cells. This localization of SpoIIIJ at the sporulation-specific septa may be important for the role of spoIIIJ during sporulation.

Performance of prohexadione-calcium on shoot growth and fruit quality of apple — Effect of spray surfactants

2008 ◽  
Vol 88 (1) ◽  
pp. 165-174 ◽  
Author(s):  
J. A. Cline ◽  
C. G. Embree ◽  
J. Hebb ◽  
D. S. Nichols
Keyword(s):  
Vegetative Growth ◽  
Shoot Growth ◽  
Management Practice ◽  
Fruit Size ◽  
Growth Control ◽  
Growth And Yield ◽  
Control Treatment ◽  
Royal Court ◽  
The Us ◽  
Prohexadione Calcium

Vegetative growth control of apples (Malus × domestica Borkh.) is necessary to maintain a balance between growth and cropping. Pruning is a labour-intensive management practice to achieve this and intrinsically stimulates new growth. Prohexadione-calcium (PC) is a plant bio-regulator that effectively regulat es the shoot extension growth of apples and other tree fruits. Previous research has demonstrated that its efficacy can vary based on the use of spray surfactants and adjuvants. This study investigated the efficacy of two rates of Apogee™, the commercial form of PC, used in combination with the spray surfactants Sylgard 309 and LI 700, on extension shoot growth and yield parameters. Experiments were conducted in Ontario on Empire and Nova Scotia on Royal Court™ Cortland apples. Treatments of 0, 75 or 125 mg L-1 PC, with and without either 0.5% (vol/vol.) LI 700 surfactant or 0.05% (vol/vol) Sylgard 309 surfactant were applied to Empire trees, and 75 or 125 mg L-1 PC, with or without 0.5% (vol/vol) LI 700, were applied to Royal Court™ trees. An untreated control treatment was also included for comparison purposes. A total of two sprays were applied to the Empire trees and a total of three sprays were applied to the Royal Court™ trees. PC significantly decreased the vegetative growth of Empire and Royal Court™ trees by approximately 18 to 44%, respectively, and the efficacy of PC was enhanced when combined with either Sylgard 309 or LI 700 surfactant. No additional benefit in vegetative growth control was gained when using Apogee™ at rates of 125 mg L-1 PC, relative to 75 mg L-1 PC. The rate of Apogee™ did not influence the number of fruit or yield per tree or mean fruit size of either cultivar. For Empire, LI 700 and Sylgard 309 significantly reduced the number of fruit per tree, resulting in lower yields and crop densities. In addition, higher mean fruit weights, and a greater distribution of fruit in the larger size categories were observed for LI 700. Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities, poorer coloured fruit, and a higher percentage of fruit less than 60 mm in diameter. These data provide support for the use of alternative surfactants with Apogee™ other than those listed on the US and Canadian product labels. Key words: Apogee™, Empire, Cortland, Regalis, calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate, surfactant

scholarly journals Pendidikan Ibu dan Durasi Pemberian Air Susu Ibu dalam Peningkatan Kecerdasan Siswa Usia Sekolah Dasar

2013 ◽  
pp. 169
Author(s):  
Maryam Said ◽  
Hadi Pratomo
Keyword(s):  
Random Sampling ◽  
Growth And Development ◽  
Education Level ◽  
Department Of Education ◽  
Cross Sectional ◽  
Systematic Random Sampling ◽  
Cross Sectional Design ◽  
High Level ◽  
Duration Of Breastfeeding ◽  
The Relationship

Riwayat pemberian Air Susu Ibu (ASI), karakteristik ibu dan anak serta pola asuh berpengaruh terhadap kecerdasan anak. Penelitian ini bertujuan untuk mengetahui proporsi tingkat kecerdasan anak, riwayat pemberian ASI, karakteristik ibu dan anak, serta faktor dominan yang berhubungan dengan tingkat kecerdasan anak pada siswa SDSN Pekayon Jaya VI Kota Bekasi. Penelitian kuantitatif dengan desain potong lintang dengan metode systematic random sampling dengan jumlah sampel sebesar 166 responden (siswa/i yang berumur 7 - 9 tahun) beserta ibunya. Penelitian ini dilaksanakan pada bulan Mei 2013. Pada siswa dilakukan tes kecerdasan menggunakan tes Raven sedangkan ibunya mengisi kuesioner. Hasil penelitian menunjukkan tingkat kecerdasan rendah 6%, rata-rata 36,7%, dan tinggi 57,2%. Variabel yang berhubungan dengan kecerdasan adalah durasi pemberian ASI dan pendidikan ibu. Pendidikan ibu adalah faktor dominan terhadap kecerdasan, bahwa ibu yang berpendidikan tinggi berpeluang mempunyai anak dengan kecerdasan tinggi yaitu 3,556 kali lebih besar dibandingkan ibu berpendidikan rendah setelah dikontrol variabel durasi ASI. Untuk Dinas Pendidikan Kota Bekasi agar menyelenggarakan berbagai aktivitas seperti seminar/pelatihan/konseling bagi orang tua murid tentang pentingnya peran orangtua terhadap tumbuh kembang anak.Breastfeeding history, mother and children characteristics, and child care are considered influential on child intellegence. This study aimed to determine the proportion of exclusive breastfeeding, the level of childrens intellegence, mother and children characteristics, the relationship between duration of breastfeeding with the level of students intellegence. This research used a cross-sectional design and through systematic random sampling with a sample size of 166 respondents (students aged 7 - 9 years old) and their mothers. The intellegence was tested using the Raven test while their mothers were interviewed. The results showed that the level of childrens intellegence was high (57.2%), average (36.7%), and low (6%). Those variables which related to the intellegence level were duration of breastfeeding and the level of mothers education. The mothers education level is one of the factors which has higher effect, againts the childrens intellegence. Those mothers who have high level education will have probability 3,556 to have their children with high level intellegence (after controlling the duration breastfeeding). Suggestion; The Department of Education Bekasi city to organize activities relevant to the improving of parents in growth and development of their children through seminars/training/counseling.      

scholarly journals The effect of the photoperiod on the level of endogenous growth regulators in pine (Pinus silvestris L.) seedlings

2014 ◽  
Vol 51 (1) ◽  
pp. 59-70 ◽  
Author(s):  
Krystyna Kriesel ◽  
Sławomir Ciesielska
Keyword(s):  
Abscisic Acid ◽  
Growth And Development ◽  
Morphological Characters ◽  
Axillary Buds ◽  
Pinus Silvestris ◽  
Low Intensity ◽  
Pine Seedlings ◽  
Terminal Bud ◽  
Development Processes ◽  
High Level

The investigations were performed on pine seedlings growing under 12, 16 and 20 hour photoperiods. In 4 succesive stages of seedling development i.e. after 2, 12, 18 and 30 weeks of culture morphological characters of the seedlings were measured and the levels of auxins-, gibberellins-, cytokininsand abscisic acid-like inhibitor were determined. The intensity of growth and development of juvenile leaves, needles and of the shoot was the lowest in plants growing under 12 hour photoperiod conditions. As the length of the photoperiod increased so did the intensity of these processes. Under the 12 hour photoperiod the development of scale leaves, axillary buds and the formation of the terminal bud started earliest. This process reached completion under the 12 hour photoperiod and the bud remained in a state of dormancy. Seedlings growing under the 12 hour photoperiod were characterized by a low level of stimulators, and at the same time by a high level of inhibitors. On the other hand in seedlings grown at 16 and 20 hour photoperiods the content of stimulators was higher and that of inhibitors lower. A high intensity of growth and development processes was correlated with a high level of stimulators while a high level of inhibitors was correlated with a low intensity of these processes.The obtained results suggest the participation of gibberellins and cytokinins in the processes of regulation of the initiation of scale leaves and axillary buds, and the participation of these hormones and of abscisic acid in the regulation of needle elongation.

Sign in / Sign up

Export Citation Format

Share Document