scholarly journals 580 GA Application Timing in Fall and Winter Influences Bloom Period, Fowering Intensity, and Final Crop in Florida `Navel' Orange

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 496C-496
Author(s):  
E.W. Stover ◽  
S.M. Ciliento ◽  
X. Yang

In Florida's subtropical climate, citrus floral induction is primarily stimulated by cool weather in the fall and winter. Frequently, inductive periods are separated by warm conditions conducive to bud development, resulting in prolonged and multiple bloom. Large variability in date of fruit-set creates an array of problems, and prolonged bloom contributes to severity of postbloom fruit drop. GA applied during the inductive period inhibits bloom in citrus. This study was conducted to determine whether different GA application timings could shift bloom intensity and duration to reduce problems associated with prolonged bloom. GA was applied via airblast sprayer to mature `Navel' on sour orange rootstock near Ft. Pierce, Fla., at 49.4 g GA/ha, 0.05% Silwet L-77, and 2340 L/HA spray volume. Six single-tree experimental units per treatment were blocked by size and vigor in a randomized complete block design. Treatments were time of GA application: 23 Nov. 1998; 17 Dec. 1998; 6 Jan. 1999; 25 Jan. 1999; 23 Nov. and 17 Dec.; 23 Nov. and 25 Jan.; 6 Jan. and 25 Jan.; and a control. Bloom began one month earlier on trees that received the two January applications compared to trees that received GA on 23 Nov. and 17 Dec.. Trees sprayed 25 Jan. (or 6 Jan. and 25 Jan.) had 2 weeks shorter bloom duration compared to controls. Total flowering on GA-treated trees ranged from 13% to 55% of the controls. Single GA applications on 17 Dec. and 6 Jan. increased fruit yield at harvest by 42% and 25%, respectively, while GA on 6 and 25 Jan. yielded 27% less than controls. All other timings had no effect on yield.

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 842G-843
Author(s):  
Aroldo Rumayor Flores ◽  
Andres Martinez C.

During 1993–94, in an area with a subtropical climate, 1500 m elevation, and 300 mm of precipitation, an experiment with `Golden Delicious' apples/MM.111 under irrigation was conducted with 11 treatments with three replications in a completely randomized complete-block design: T1, manual defoliation (27 Sept.); T2, 1% CuSO4 (15 Oct.); T3, 2% CuSO4 + Promesol (acido 2,3,4 trihydroxipentanodioico) (22 Oct.); T4, 1% CuSO4 + 0.1% Atlox; T5, 1% CuSO4 + 0.2% Atlox; T6, 1% CuSO4 + 0.1% Frigate; T7, 1% CuSO4 + 2% urea; T8, 2% sulfur; T9, 500 ppm tiadizuron + 1% carboxil; T4–T9, defoliation 12 Nov.; T10, control (natural defoliation on 3 Dec.); T11, 2% ZnSO4 + 0.07 carboxil (8 Nov.). All treatments received Atlox surfactant at 0.1%, except T4 and T5. On 11 Mar. 1994, trees received an application of 0.5% Dormex + 4% dormant oil. The percentage of terminal budbreak on 1-year-old wood was superior for T6, T9, and T11 compared with the control (11.7% budbreak on 2-year-old wood) for all treatments (except T1 and T3); all the treatments were superior to the control (47% budbreak), especially T2 (72.6%) and T9 (70.0%). The percentage of fruit set was similar in all treatments with the control (15.0%), except in T2 and T3, which set 7% more fruit.


Author(s):  
Nasratullah Habibi ◽  
Friba Sikandari

An experiment was conducted to evaluate effect of urea fertilizer on yield and yield components of Zea mays L. Using Randomized Complete Block Design (RCBD) split plots in three replications in agricultural research farm of Balkh University by 2019. Doses of urea used in this experiment were 0, 80, 160 and 240 kg ha-1 , respectively. It has been found that amount of nitrogen fertilizer (urea) had significant effect on yield of maize at p<0.05. The higher level of nitrogen caused the higher grain yield, number of kernels per ear, the number of grains per ear row, ear diameter, cob length, grain per plant and plant height. As a result 7.76 ton ha-1 was recorded as high yield while 240 kg ha-1 urea was used, and 5.12 ton ha-1 was recorded as low yield in treatment one with 0 kg ha-1 of nitrogen fertilizer. Finally, as a result using 240 kg ha-1 nitrogen fertilizer is recommended.


Revista CERES ◽  
2018 ◽  
Vol 65 (4) ◽  
pp. 314-320
Author(s):  
Núbia Maria Correia ◽  
Agnaldo Donizete Ferreira de Carvalho

ABSTRACT When selecting a weed chemical treatment (herbicide, product mixtures, dose, or application timing), an important issue to consider is its selectivity to the crop of commercial interest. The objective of this study was to evaluate the selectivity of the herbicide metribuzin to carrot plants as a function of genotype, dose, and plant growth stage at the time of application. Two experiments were carried out, one in a greenhouse and another in the field. The greenhouse experiment was arranged in a completely randomized, 5 x 2 x 3 factorial design, with four replications. Metribuzin doses (0, 72, 96, 144, and 192 g ha-1) were sprayed on plants with 2-3 and 4-5 true leaves of the cultivars Maestro, BRS Planalto, and Verano. Cultivar Maestro was cultivated in the field in a 2 x 5 factorial experiment in randomized complete block design, with four replications. Carrot plants, at two stages of development (2 and 5 true leaves), were sprayed with the same doses of metribuzin applied in the greenhouse experiment. Metribuzin, regardless of application time and dose tested, was selective for cultivars BRS Planalto and Verano (greenhouse) and Maestro (both greenhouse and field), without reduction in quality and yield of roots.


HortScience ◽  
1996 ◽  
Vol 31 (5) ◽  
pp. 760g-761
Author(s):  
Jonathan R. Schultheis ◽  
Dennis E. Adams

Boron has been used to overcome the disorder blister in varieties such as `Jewel'. `Hernandez' is an attractive, good-yielding variety with uniform shape that will consistently pack out at 80% to 90%. Over time in storage, however, roots develop blister-like symptoms, rendering roots unmarketable for fresh market. Our objective was to evaluate the effect of different B rates and application times on the yield and quality of `Hernandez' roots. Rates were varied up to 2.24 kg actual B/ha 6 days after planting, while various soil and foliar application times (6, 34, and 69 days after planting) were evaluated at 1.12 kg·ha–1. In 1994, three row plots were arranged in a randomized complete block design and replicated four times. Planting was on a deep sand to maximize the effect of the B carrier Solubor. Roots were harvested, graded, and weighed 120 days after planting and storage roots evaluated for blister-like symptoms in Mar. 1995. No significant differences in yield were attributed to B rate or application method. Blister-like symptoms were more severe when no B was applied; however, application of B did not eliminate symptoms, as most roots had the blister-like appearance. Boron application did not solve the problem, but symptoms were less apparent when some B was applied.


1969 ◽  
Vol 90 (3-4) ◽  
pp. 183-191
Author(s):  
Miguel Espitia-Camacho ◽  
Franco A. Vallejo-Cabrera ◽  
Diosdado Baena-Garcia ◽  
Linda Wessel-Beaver

Path coefficient analysis was carried out in tropical pumpkin (Cucurbita moschata Duchesne) for yield per plant as a function of number of fruit per plant and weight per fruit, using phenotypic and genetic correlations from two diallels: one using five varieties (variety diallel) and a second using five S1 lines derived from the varieties (line diallel). A randomized complete block design with five replications was used to evaluate 15 genotypes from each diallel, not including reciprocals. Direct effects were 300 to 500% greater than indirect effects in the line diallel. In contrast, direct effects were only 17 to 68% greater than indirect effects in the variety diallel. Effects (direct and indirect) were greater (17 to 500%) when genetic correlations rather than phenotype correlations (42 to 440%) were used in the path analysis. Fruit weight showed a greater effect on yield than did number of fruit, with values between 3.2 to 4.9 times the residual effects. Fruit weight and number of fruit can be used as selection criteria to increase yield in tropical pumpkin.  


Author(s):  
Sabrina Raquel Griebeler ◽  
Mateus Pereira Gonzatto ◽  
Gerson Nestor Böettcher ◽  
Leonardo André Schneider ◽  
Manuela Sulzbach ◽  
...  

Abstract: The objective of this work was to evaluate the number of successive applications of gibberellic acid (GA3), during the autumn-winter period, for its effect on the reduction of flowering, in the subsequent spring after periods of low fruit load (off-year), in 'Montenegrina' mandarin trees (Citrus deliciosa). Sequential applications at 40 mg L-1 GA3 were tested from one to four times, at 21-day intervals, beginning in the end of May. The experiment was carried out in a randomized complete block design, with four treatments and a control, four replicates, and one plant per experimental unit. Flowering, sprouting, types of shoots, fruit set, and fruit diameter were evaluated. The fruit set increases exponentially with the reduction of flowering intensity. The use of GA3 in two, three, or four sequential applications, from May to June, May to July, and from May to August, at 21-day intervals, reduces the intensity of flowering and sprouting of alternate bearing plants in the subsequent spring, increasing mixed shoots and reducing floral shoots. The use of four sequential applications of 40 mg L-1 GA3 promotes a great increase in the frequency of single flower terminal leafy shoots and favors the increase of fruit fixation and size.


2018 ◽  
Vol 36 (0) ◽  
Author(s):  
A. KALSING ◽  
F.R. LUCIO ◽  
C.V.S. ROSSI ◽  
P.E. RAMPAZZO ◽  
F.P. GONÇALVES ◽  
...  

ABSTRACT: The DAS-444Ø6-6 soybean expresses AAD-12, 2mEPSPS and PAT enzymes to provide, respectively, tolerance to 2,4-D, glyphosate and ammonium glufosinate. This event is also associated with DAS-81419-2 expressing Cry1Ac and Cry1F proteins to provide protection against a broad spectrum of soybean lepidopteran insect species. Successful adoption by growers of these technologies relies on the traits performing in the diverse environments of Brazil, especially under adverse weather conditions. The objective of this study was to characterize the tolerance of DAS 444Ø6-6 and DAS-444Ø6-6 x DAS-81419-2 soybeans to 2,4-D and glyphosate in the Cerrado region of Brazil. Eight trials across four sites were conducted in the 2015/2016 summer rainy season using a randomized complete block design, with a factorial arrangement of treatments. Factor A was 2,4-D choline salt (456 g a.e. L-1) + glyphosate DMA salt (480 g a.e. L-1) at 975 + 1,025 and 1,950 + 2,050 g a.e. ha-1, respectively and ready-mix of (2,4-D choline salt 195 g a.e. L-1 + glyphosate DMA salt 205 g a.e. L-1) at 2,000 (975 + 1,025) and 4,000 (1,950 + 2,050) g a.e. ha-1. Factor B was application timing at V3, V6 and R2 soybean growth stages. No visible symptoms of leaf chlorosis, epinasty, or growth inhibition were observed. Slight leaf droop was observed at 1 day after treatment (DAT), but it was null at 7 DAT. Less than 6% and 13% of leaf necrosis or injury were observed at 7 DAT, respectively, at 975 + 1,025 and 1,950 + 2,050 g a.e. ha-1 of 2,4-D choline salt + glyphosate DMA salt, regardless of applied as a ready-mix or not, but it was always 2% or less at 28 DAT. Crop grain yield was not influenced by herbicide treatments, application timing and their interaction, regardless of the soybean event and experimental site. DAS-444Ø6-6 and DAS-444Ø6-6 x DAS-81419-2 soybeans showed high tolerance to 2,4-D choline salt and glyphosate DMA in the Cerrado region of Brazil.


2019 ◽  
Vol 3 (3) ◽  
pp. 16-24
Author(s):  
Ni Komang Alit Astiari ◽  
Ni Putu Anom Sulistiawati ◽  
Ida Bagus Komang Mahardika ◽  
I Nyoman Rai

This research was carried out at Kintamani District, Bangli Regency, Bali-Indonesia, from February to October 2019 with aimed to overcome the failure of fruit-set and fruit drop of Siam orange on off-season period through application of mycorrhizal inoculants and ZnSO4 micro fertilizer dosage. This experiment was arranged as a randomized block design consisted of 2 factors.  The first factor was mycorrhizal inoculant (0, 50, 100 and 150 g/tree), while the second factor was the dosage of ZnSO4 micro fertilizer (0, 5, 10 g/tree). All treatments were repeated 3 times. The results showed that the interaction between mycorrhizal inoculant treatment and ZnSO4 micro fertilizer dosage did not significantly affect all of the variables observed.  Mycorrhizal inoculant dose 150 g/tree could overcome the failure of fruit-set and fruit drop and improved the quantity and quality of fruit of Siam oranges on off-season, which was reflected by increased number of fruits harvest per tree (249,00 fruits), weight per fruit (106,10 g), weight of fruit harvested per tree (26,34 kg) and total dissolved solids (13.52% Brix), or increase 31,44%; 18,15%; 54,58%; and 35,74%, respectively, compared to without mycorrhizal inoculant i.e 189,44 fruit; 17,04 kg; 89,80 g and 9,96% Brix.


2020 ◽  
Vol 9 (3) ◽  
pp. 81
Author(s):  
DOAH DEKOK TARIGANS

<p>i-ow productivity of coconut farm is the main problem of coconut industry. The fact that intercropped palms were more productive than when solely planted, the most suitable way to increase productivity is through multiple cropping. To cope with (he existing variation of cropping pattern in relation to coconut production, soil and leaf nutrient element, various cropping patterns with four species of perennial crop as intercrops were conducted under study. The objectives of the study were (1) to study the effect of cropping patterns on the growth, nut production and farm productivity of coconut under farmer levels, soil chemical propeties and leaf nutrient element and (2) to study the correlation between growth and production parameter with soil chemical propeties and leaf nutrient elements. Various cropping patens under study namely (1) coconut monoculture (control), (2) coconut + pineapple, (3) coconut + coffee, (4) coconuf - papaya ♦ pineapple, (5) coconut + banana + coffee, and (6) coconut + banana + papaya + coffee i pineapple Total area for each cropping patern was 0.5 ha with coconut planting distance 8 m x 10 m and the palms 35-40 years old The site of the experiment conducted was at Silang, Cavite. Data on coconut growth and production, soil chemical properties and leaf nutrient parameters, were statistically analyzed in a randomized complete block design (RCDB) with three replications. Correlation analysis were performed on the following (1) Growlh and production parameters with soil chemical propeties, and leaf nutrient elements, (2) Relationship among nutrient element in the coconut leaves under various cropping paterns Results of the study showed that the effect of cropping patterns on the number of full-grown nul increased signiicantly more nut and higher amounts of copra per tree were produced in intercropped farms than in the mono-cropped coconut plantation. These increase ranged from 64 to 98 percent in terms of nuts and 70 to 105 percent in terms of copra. Positive correlation was observed between nitrogen in the top soil with weight of copra and nut production. The exchangeable potassium in lop soil was positively correlated with nut production. Meanwhile, the organic mater, content in the soil were positively correlated with weight of copra, nut production but negatively correlated with percentage of nul shedding. These results implies that increase organic matter content in the soil will increase coconut production including fruit set Nitrogen concentration in the leaf was positively and highly signiicantly correlated with number of nut shedding These finding suggested that the increased nitrogen concentration in the leaf greatly promotes nul production and fruit set of the palms under various cropping patterns in coconut The potassium in the leaf was significantly correlated with nul production but negatively correlated with percentage of nut shedding. Key words: Coconut production, cropping patterns, soil chemical, leaf nutrient elements, correlation<br /><br /><strong>RINGKASAN </strong></p><p><strong>Produksi kelapa pada beberapa pola tanam dan hubungannya dengan kandungan unsur hara tanah dan daun kelapa</strong></p><p>Rendahnya produktivitas tanaman merupakan masalah utama pada perkebunan kelapa. Salah satu cara untuk meningkatkan produktivitas yaitu melalui penerapan usahatani kelapa campuran. Suatu kenyataan bahwa penerapan intercropping menyebabkan tanaman kelapa lebih produktif dibandingkan dengan tanaman monokultur. Untuk mengetahu sejauh mana pengaruh tersebut secara ilmiah, serta hubungannya terhadap unsur hara tanah dan unsur hara dalam daun kelapa maka dilakukan penelitian secara terencana pada pertanaman kelapa rakyat produktif. Tujuan penelitian ini (1) untuk mengetahui pengaruh pola tanam terhadap petumbuhan dan produksi tanaman kelapa, terhadap unsur hara dalam tanah dan kadar hara daun kelapa dan (2) mcmpelajari korelasi antara parameter petumbuhan dan produksi kelapa dengan hara tanah serta kadar unsur hara daun. Enam polatanam kelapa yang diuji dalam penelitian ini yaitu (1) kelapa monokultur, (2) pola tanam kelapa + nanas, (3) pola tanam kelapa * kopi, (4) pola tanam kelapa + papaya + nanas , (5) pola tanam kelapa + pisang ♦ kopi dan (6) pola tanam kelapa + pisang + papaya ♦ kopi + nanas dimana masing-masing pola tanam seluas 0.5 ha. Jarak tanam kelapa 8 m x 10 m, dengan umur 40-45 tahun. Penelitian dilakukan di Silang, Cavite. Penelitian menggunakan rancangan acak lengkap (randomized complete block design) dengan tiga ulangan. Parameter yang diamali meliputi jumlah daun, jumlah bunga betina (button) per tandan, kadar unsur hara tanah meliputi kandungan bahan organik, pH, CEC, Nitrogen, Phosphor, Calcium, dan Magnesium. Sedangkan unsur hara daun yaitu Nitrogen, Phosphor, Calsium, dan Magnesium. Analisis korelasi dilakukan terhadap (1) pertumbuhan dan produksi kelapa dengan unsur hara tanah, dan unsur hara daun dan (2) hubungan antar unsur hara daun kelapa pada beberapa polatanam kelapa yang ditclili. Hasil penelitian menunjukkan bahwa produksi buah dan kopra pada polatanam campuran lebih tinggi dibandingkan dengan hasil pola tanam kelapa monokultur. Peningkatan produksi buah 64-98 persen dan kopra 70-105 persen. Kadar nitrogen pada lapisan atas tanah mempunyai korelasi positif dengan berat kopra dan produksi buah. Sedangkan unsur kalium pada lapisan tanah yang sama mempunyai korelasi positif dengan produksi buah kelapa Kandungan bahan organik tanah mempunyai korelasi positif dengan berat kopra, produksi buah namun berkorelasi negatip dengan presentase buah yang gugur (nut shedding) Hasil ini berimplikasi bahwa dengan meningkatnya kadar bahan organik tanah akan meningkatkan produktivitas tanaman kelapa. Lebih lanjut, hasil penelitian menunjukkan bahwa kadar nitrogen dan kalium pada daun mempunyai korelasi positif dengan peningkatan produksi kelapa dan persentasi buah yang jadi.</p><p>Kata kunci: Produksi kelapa, polatanam, unsur hara tanah, kadar unsur daun, analisis korelasi</p>


2018 ◽  
Vol 2 (1) ◽  
pp. 49
Author(s):  
Muhamad Syukur ◽  
Sobir . ◽  
Awang Maharijaya ◽  
Syarifah Iis Aisyah ◽  
Dewi Sukma ◽  
...  

Cabai (Capsicum annuum L.) have various in fruit shapes, fruit colors, fruit types, hot tasty and biochemical compound useful for fresh fruit, spicy and ornamental plant. Ornamental chili ideotype that are dwarf, high fruit set and various fruit colors. The aim this study to improve description characters in Ayesha IPB variety, both qualitative and quantitative characters. The testers are 4 released varieties and 5 the other genotypes in randomized complete block design for 4 replication in green house at Leuwikopo field reserch in Darmaga, Bogor. Ayesha IPB variety showed early flower in 13-16 days after planting, harvesting for commercial bucket in 65-70 days after planting, medium plant high that is 25.218 cm, medium canopy width that is 46-53 cm, good performance in canopy, round shape on fuit tip, various fuit colors that are  yellow green for young fruit, orange for intermediate fuit and orange red for mature of fruit. Those description characters could be ornamental chili for Ayesha, so it is important to protect the plant for ornamental plant commercialization.Key word : fruit, color, red,  round, orange, ornamental


Sign in / Sign up

Export Citation Format

Share Document