Nitrogen and environmental factors influencing macadamia quality

2000 ◽  
Vol 40 (8) ◽  
pp. 1145 ◽  
Author(s):  
R. A. Stephenson ◽  
E. C. Gallagher ◽  
V. J. Doogan ◽  
D. G. Mayer

Applications of nitrogen fertiliser in macadamia orchards remain high, despite indications that optimum yields and quality are obtained at a lower rate. This 6-year study examined the effect on quality of 230, 690 and 1150 g nitrogen/tree . year, applied in April (floral initiation), in April and June (inflorescence development), in April, June and November (rapid nut growth and premature nut drop), in April, June, November and January (nut maturation/oil accumulation) or monthly. Higher rates of nitrogen increased kernel recovery by 1% in 5 years out of 6. In 1 year only, 4 or more split applications of the medium and high rates of nitrogen increased kernel recovery by up to 1.6%. These increases were insufficient to compensate for depressed yields (17% lower) at high nitrogen. In good years, when yields were above average, kernel recovery tended to be high and in years with poor yields, kernel recovery tended to be low except when nuts were small. Moderate summer—early autumn rainfall of about 100 mm/month was associated with high kernel recovery whereas very heavy rainfall (>200 mm/month) during this period was detrimental. The percentage of first grade kernels was influenced most by season but was negatively correlated with the rate of nitrogen. Impurities, including immature, deformed, mouldy and insect-damaged kernels, were lowest at low rates of nitrogen and highest during wet harvest seasons. Time of nitrogen application had no significant effect on yield, kernel recovery, the percentage of first-grade kernels or impurities. For sustained high yield and quality, 355 g nitrogen, or 0.8 kg urea/tree.year, applied in April—June is indicated. Agronomic and economic advantages of reducing rates of nitrogen applied to macadamia orchards are enhanced by increasingly important environmental considerations. Multiple regression analyses indicated that the rate, strategy and timing of nitrogen application, rainfall, temperature, flushing and litterfall were correlated with kernel recovery and first-grade kernels but more work is needed to elucidate the significance of these factors.

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 614c-614
Author(s):  
A.M. Akl ◽  
A.M. Wassel ◽  
F.F. Ahmed ◽  
M.A. Abdel Hady

This investigation was conducted during the 1991, 1992, and 1993 seasons to study the effect of different concentrations and number of sprays urea and/or boric acid on yield and berries quality of Red Roomy grapevines. Two, three, four, or five sprays for both urea at 0.5% 1%, or 1.5% and /or boric acid at 0.1%, 0.2%, or 0.3% in addition to the control treatment were applied. Combined sprays of urea and boric acid was preferable in increasing the number of clusters, yield per vine, berry set parentage, fertility coefficient. weight, length and shoulder of cluster, weight and dimensions of berry, total soluble solids, total sugars, and total anthocyanins in grapes and in reducing the percentages of cracked and shot berries and the total acidity compared with the single application of both. Spraying urea at 1.0% in combined with boric acid at 0.2% four times (i.e., at growth start, first bloom, immediately after berry set, and at 30 days later) is recommended for achieving high yield and fairly good berries quality in `Red Roomy' grape vines.


Author(s):  
Tayyaba Samreen ◽  
Muhammad Imran ◽  
Zahir Ahmad Zahir ◽  
Muhammad Zulqernain Nazir ◽  
Saima Noureen ◽  
...  

2014 ◽  
Vol 83 (2) ◽  
pp. 105-111
Author(s):  
Izumi Tsujita ◽  
Hiroshi Kimura ◽  
Takashi Yudate ◽  
Kenichi Yamaguchi

Author(s):  
Fakhrusy Zakariyya ◽  
Adi Prawoto

An optimum physiological condition will support high yield and quality of cocoa production. The research was aimed to study the effects of stomatal conductance and chlorophyll content related to cocoa production under three shade regimes.This research was conducted in Kaliwining Experimental Station, elevation of 45 m above sea level with D climate type based on Schmidt & Fergusson. Cocoa trees which were planted in 1994 at a spacing of 3 X 3 m were used in the study planted by using split plot design. The shade tree species were teak (Tectona grandis), krete (Cassiasurattensis), and lamtoro (Leucaena sp.) as the main plots, and cocoa clones of Sulawesi 01,Sulawesi 02, KKM 22 and KW 165 as sub plots. This study showed that there was interaction between cocoa clone and shade species for stomatal conductance where stomatal diffusive resistance of KKM 22 was the best under Leucaena sp.and Cassiasurattensis with the values of 1.38 and 1.34 s.cm -1, respectively. The highest chlorophyll content, stomatal index and transpiration values was under Leucaena sp. shade. There was positive correlation between chlorophyll content and transpiration with pod yield of cocoa. The highest yield and the lowest bean count wereobtainedon Sulawesi 01 clone under Leucaenasp. shade.Keywords: stomatal conductance, transpiration, diffusive resistance, shades trees, clones,pod yield


AGROFOR ◽  
2018 ◽  
Vol 3 (1) ◽  
Author(s):  
S.F. EL-SAYED ◽  
A.A. GAHRIB ◽  
Rasha R. EID

This investigation was carried out during the two summer seasons of 2015 and2016 in sandy soil on potato culitvar "Sante" to study the effect of using 100%compost (15 t/fed.) and 50% compost + nitrogen fixing bacteria (Azotobacter, andPseudomonas alone or together) on potato yield and quality as compared to theconventional mineral fertilization (120-75-150 kg/fed. NPK + 5 toncompost/fed.(control)). No significant differences in tubers yield/fed. were detectedbetween mineral fertilization (control) and using 100% compost (15t/fed).However, control treatment significantly produced a high yield per feddan,more than using 50% compost + any biofertilizer treatment.Using composttreatment at 15 t/fed.execeed all biofertilizer treatments in marketable yield in bothseasons, but without significant differences as compared with mineral fertilization(control).No significant differences in tuber dray matter and content of starch intuber were found between using compost treatment at 15 ton/fed. and mineralfertilization treatment (control)in both seasons. Nevertheless, application of 50%compost+ 4 applications of Azotobacter and Pseudomonas had the highest tuberconcentrations of starch and nitrogen with significant differences as compared withthe mineral fertilization.Using50% compost + 4 applications of Azotobacter orPseudomonas or both (Azotobacter + Pseudomonas )and application of 100%compost caused producing potato tubers with the lowest concentration of nitratewith significant differences as compared with the mineral fertilization. Nosignificant differences were detected between mineral and organic fertilizersconcerning P and K concentrations in tubers.


1999 ◽  
Vol 2 (3) ◽  
pp. 722-724
Author(s):  
M. Ayub . ◽  
I. A.P. Dewi . ◽  
A. Tanveer .

2018 ◽  
Vol 47 (1) ◽  
pp. 183-193 ◽  
Author(s):  
Tuncay TURSUN ◽  
Sener AKINCI ◽  
Esin BOZKURT

Boron is an important micronutrient, required for all plant growth, and critical for high yield and quality of crops. The aim of the present research was to determine the effects of boron on pot-grown parsley (Petroselinum sativum Hoffm.). The experimental design consisted of four treatments using Hoagland-Arnon (1950) nutrient solutions with two different boron concentrations (B1 - 15 ppm and B2 - 150 ppm), each with and without 10 ml humic acid addition (HB1 and HB2), and controls with full strength Hoagland-Arnon solutions. Growth analyses of the parsley revealed that 15 ppm boron application caused an increase in root length leaf fresh and dry weight root fresh and dry weight and leaf area compared to control values. 150 ppm B (B2) concentration decreased all growth parameters compared to controls. The two humic acid treatments (HB1 and HB2) did not increase any of those growth parameters either in controls (C) or in the two boron (B1 and B2) concentrations. Analysis by (ICP-MS) revealed that B content in the leaves increased gradually in B1 and B2, as well as in both humic treatments where in HB2 it increased to 99.38% compared to B1. In the leaves, Mn, Zn and Fe contents behaved the same as B, increasing in all treatments, with the amounts in HB2 being significantly greater than in C, B1 and B2 leaves.


2020 ◽  
Vol 54 (6) ◽  
pp. 536-545
Author(s):  
Jussi Helppi ◽  
Ronald Naumann ◽  
Oliver Zierau

One of the most commonly used protein sources in rodent diets is soy, which is naturally rich in phytoestrogens. Although phytoestrogens have shown potential health benefits in humans, they may also have the ability to disrupt reproduction. Consequently, there has been a tendency to try to exclude them from rodent diets. In the current study, we investigated whether phytoestrogen content in the mouse diet could affect reproduction in mice used as embryo donors. Donor mice (C57BL/6JOlaHsd) were maintained with three different diets: high phytoestrogen (ca. 400 mg/kg genistein), low phytoestrogen (ca. 10 mg/kg genistein) and standard breeding diet (ca. 120 mg/kg genistein). Mice fed a high phytoestrogen diet had a high yield of plugs, embryos, and injectable embryos, as well as producing good quality embryos. Results from donor mice fed a low phytoestrogen diet were consistently but only slightly inferior, whereas mice fed a standard diet performed the poorest. Interestingly, the largest number of born and weaned offspring were observed when recipient females received embryos from the standard diet group. Sperm yield and quality of stud males did not differ between the groups. We surmize that for experimental endpoints requiring fertilized embryos it may be more beneficial to feed mice a diet containing phytoestrogen, but if the goal is to produce transgenic mice, a diet high in phytoestrogen may be inadvisable. In conclusion, care should be taken when selecting a diet for experimental mouse colonies as phytoestrogen could influence the study outcome.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Juansheng Ren ◽  
Fan Zhang ◽  
Fangyuan Gao ◽  
Lihua Zeng ◽  
Xianjun Lu ◽  
...  

AbstractThe yield heterosis of rice is sought by farmers and strong contributes to food safety, but the quality of hybrid rice may be reduced. Therefore, developing new varieties with both high yield and good quality is a heavily researched topic in hybrid rice breeding. However, the molecular mechanism governing yield heterosis and high rice quality has not been elucidated to date. In this study, a comparative transcriptomics and genomic analysis was performed on a hybrid rice variety, Chuanyou6203 (CY6203), and its parents to investigate the molecular mechanism and gene regulation network governing the formation of yield and quality stages. A total of 66,319 SNPs and InDels between CH3203 and C106B were detected in the 5′-UTR, exon, intronic, and 3′-UTR regions according to the reference genome annotation, which involved 7473 genes. A total of 436, 70, 551, 993, and 1216 common DEGs between CY6203 and both of its parents were identified at the same stage in panicles and flag leaves. Of the common DEGs, the numbers of upregulated DEGs between CY6203 and CH3203 were all greater than those of upregulated DEGs between CY6203 and C106B in panicles and flag leaves at the booting, flowering, and middle filling stages. Approximately 40.61% of mRNA editing ratios were between 0.4 and 0.6, and 1.68% of mRNA editing events (editing ratio ≥ 0.8) in CY6203 favored one of its parents at three stages or a particular stage, suggesting that the hypothetical heterosis mechanism of CY6203 might involve dominance or epistasis. Also 15,934 DEGs were classified into 19 distinct modules that were classified into three groups by the weighted gene coexpression network analysis. Through transcriptome analysis of panicles and flag leaves in the yield and quality stages, the DEGs in the green-yellow module primarily contributed to the increase in the source of CY6203 due to an in increase in photosynthetic efficiency and nitrogen utilization efficiency, and a small number of DEGs related to the grain number added spikelet number per panicle amplified its sink. The balanced expression of the major high-quality alleles of C106B and CH3203 in CY6203 contributed to the outstanding quality of CY6203. Our transcriptome and genome analyses offer a new data set that may help to elucidate the molecular mechanism governing the yield heterosis and high quality of a hybrid rice variety.


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