Promote growth by Chitosan oligosaccharide

Indoleacetic acid is a very important growth hormone in plants, which is closely related to root development.

The application of chitooligosaccharides can induce the increase of secretion of plant growth hormones such as indoleacetic acid in plants.

The results of the study showed that after using Chitosan oligosaccharide, plant endogenous hormones such as indoleacetic acid and gibberellic acid reached the highest levels within 8 hours.

HUANGLONGBING

Life form: Bacterium

Origin: Asia and Africa 

Distribution: Varies, depending on the species

Features: Yellowing, blotchy mottling and unseasonal leaf  flushing, leaf drop, dieback of branches .

Pathways: Imported plant propagative material, infected insects

At risk: Commercial citrus varieties & relatives

Huanglongbing (yellow dragon disease), previously known as citrus greening disease, is one of the worst diseases of citrus trees worldwide. It is caused by the bacterial disease Candidatus Liberibacter asiaticus that spreads through the tree canopy, causing decline and then death of the tree.

There is no cure – the only way to stop the disease is to destroy all infected trees and replace them.

The disease huanglongbing originated from China, with its vectors from Asia (Asiatic citrus psyllid) and Africa (African citrus psyllid). Depending on the species, the disease and its vectors can now be found throughout:

  • North, Central and South America
  • South East Asia, including Indonesia and East Timor
  • Papua New Guinea.

The islands of Torres Strait provide a potential pathway for the movement of serious pests into Australia, such as huanglongbing and the Asian citrus psyllid, present in countries to our north.

How to identify Huanglongbing (Candidatus Liberibacter asiaticus)

Everyone needs to keep an eye out for symptoms of huanglongbing.

Huanglongbing is spread by the movement of infected plants and plant propagative material and by sap sucking insects. These insects – the Asiatic citrus psyllid (Diaphorina citri) and African citrus psyllid (Trioza erytreae) – are not present in Australia and are of major concern due to their ability to spread huanglongbing.

  • Adults of the Asiatic citrus psyllid are 3-4 millimeters long with brown markings on the wings. When feeding on the veins of the young leaves, they adopt a ‘head-down, tail-up’ position.
  • Juvenile psyllids are yellow and commonly found feeding on young, soft shoots.

The African citrus psyllid is similar but larger with a light brown-grey body and black head, and large transparent forewings.

Psyllids

Psyllids

Huanglongbing causes yellowing of citrus plant leaves and in some instances deformed, sour and bitter fruit.

  • Symptoms on leaves are subtle and hard to pick but one key sign is a blotchy yellowing that is not symmetrical or mirrored on both sides of the leaf.
  • Later, new young leaves are small, upright and yellow, with green bands around the veins.

In well-managed orchards, a yellowing that spreads slowly over the tree and through an orchard is an easily seen sign. The spreading yellowing effect can be especially hard to see in neglected backyard citrus trees growing in poor soils.

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Infected trees have a blotchy yellowing that is not symmetrical or mirrored on both sides of the leaf Source: DAWR

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Fruit from infected trees can be misshapen or lopsided, and when cut lengthwise, the arrangement of internal tissues may be irregular Source: DAWR

Herbicide efficacy enhancer-Methylation Vegetable oil

Methylation Vegetable oil can improve the spreading area, adhesion and permeability of droplets on the surface of the crop, and promote the absorption and conduction in crop.

Besides, the methylated vegetable oil can prevent the liquid droplets from drying too fast, thereby enhancing the absorption of droplets through pores and the stratum corneum, and enhances efficacy for herbicides.

Tea Saponin-natural extract

Tea Saponin, a glycoside compound extracted from camellia tea seeds, is excellent natural nonionic active surfactant. It can be widely used in pesticide, cultivation, textile, daily chemicals, arthitectural field, medical field and so on.

Tea saponin is triterpenoid saponin, it tastes bitter and spicy. It stimulates mucous membrane of nose to lead to sneeze. The pure product is fine white column-shape crystalloid with strong moisture absorption ability. It presents apparent acidity to methyl red. It’s easy to be dissolved in water, water-contained methanol, water-contained ethanol, glacial acetic acid, acetic anhydride and pyridine etc. Its melting point: 224.

CAS NO.: 8047-15-2

MOLECULAR FORMULATE: C57H90O26

Content: 60%-65% 

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DMU – Dimethylolurea

Chemical name : N,N’-Dimethylolurea
Formula : C3H8N2O3
Molecular Weight : 120.1
CAS No. : 140-95-4

QQ图片20181019094853

Dimethylolurea is used to treat textiles and wood, and is mixed with fillers for use in molding adhesives. And used in disinfectants and other biocidal products, as an in-can preservative, as a preservative for liquid-cooling and processing systems, and as a slimicide. Dimethylolurea is also used as a preservative in metal-working fluids, as a developer of photographic film, and as a cleaning agent and disinfectant.

Mepiquat chloride for cotton

Mepiquat chloride and mepiquat pentaborate both contain mepiquat which is an anti-gibberellin growth retardant that reduces plant cell enlargement to help balance vegetative and reproductive growth.

When applied to cotton, it can help control rank growth by reducing stem elongation at newly formed internodes.

The application of PGRs can help increase fruit retention and promote earlier maturity, reducing the crop’s risk of late-season insect damage, boll rots, and harvest losses.

Mepiquat applications have been linked to increased cotton yield potential when applied at the optimum rate and timing for the variety and field planted.

The effect of Ascophyllum nodosum extract on the growth, yield and fruit quality of tomato grown under tropical conditions

Tomato plants (Lycopersicum esculentum Mill) grown under tropical field conditions were treated with an alkaline seaweed extract made from Ascophyllum nodosum (ASWE).

Two field experiments and one greenhouse experiment were conducted to evaluate methods of application, dosage of application, and the impact of each on plant growth parameters and on the quality and yield of fruit.

Field experiment 1 included 0.2 % ASWE spray, 0.2 % ASWE root drench, fungicide spray and combinations of the above. Plants foliar-sprayed with 0.2 % ASWE had significantly increased plant height (10 %) and plant fruit yield (51 %) when compared to control plants. Similar results were observed for ASWE spray alternated with fungicide or with ASWE root drench. Field experiment 2 included 0.5 % ASWE spray, fungicide spray and ASWE spray alternated with fungicide. The higher concentration of ASWE resulted in a significant increase in plant height (37 %) and plant fruit yield (63 %) compared to control plants. The third experiment under greenhouse conditions also showed that 0.5 % ASWE spray caused a significant increase in plant height (20 %) and plant fruit yield (54 %) compared to control plants.

In the greenhouse, ASWE-treated plants had larger root systems and increased concentrations of minerals in the shoots. Fruit from plants treated with ASWE showed significant increases in quality attributes including, size, colour, firmness, total soluble solids, ascorbic acid levels and mineral levels.

Overall, the use of ASWE resulted in clear improvements in tomato fruit yield and quality under tropical growing conditions.

 

Content from https://link.springer.com/article/10.1007/s10811-015-0608-3

Effect of jasmonates on coloration and quality of the‘Christmas Rose’ grape berry

Objective:

TheChristmas Rosegrape is a type of the late-maturing cultivars which is widely planted in China. It is favored by consumers because of its delicate fleshresistance to storage and transportationand high quality. Howeverin some areasthe coloration of theChristmas Rosegrape was not very good because of high temperature and humiditywhich affected its internal and external qualities. In recent yearsresearchers found that jasmonateswhich widely exist in plantscould improve coloration of fruit by promoting the accumulation of anthocyanin. This study is to explain the effect of different concentrations of exogenous prohydrojasmon(PDJ)methyl jasmonate(MeJA) on the coloration and quality of theChristmas Rosegrape so as to provide some theoretical evidence to improve coloration and quality of this grape berry.

Methods:

The trial was conducted at the experimental farm of the Zheng⁃zhou Fruit Research InstituteCAASon uniform 6- year- oldChristmas Rosegrapevines. All treatments were applied in three replications and arranged in a complete randomized block designwith a single grapevine for each replication. Two different concentrations (10 mg·L– 150 mg·L– 1) of prohydrojasmonmethyl jasmonate were respectively applied to theChristmas Rosegrape berries. The aqueous solutions of both treatments and control involved 0.1% Tween-80 and 1% ethanol. The experimental grape berries were sprayed uniformly with aqueous solution twice at the beginning of veraison and 7 days later after the first application. After the first treatmentsamples were taken every 10 days until the fruit was ripe when the seeds were completely brown and the soluble solids content no longer increased. A total of 40 single berries from the topmiddle and bottom parts of randomly selected 10 grape bunches were picked and brought to the laboratory for analysis. The coloration of the grape berry was measured by a Minolta colorimeter and expressed as the value (the fruit surface light brightness) value (color component of red and green) value (color component of yellow and blue) and CIRG value (color index of red grape). Anthocyanin content in the skin extraction was measured by the pH differential method. The contents of chlorophyll a and chlorophyll b in the skin extraction were tested according to the Arnons method. The soluble solids content of the fruit was measured by a PR-101 refractometer. The titratable acid in the grape juice was titrated by 0.1 mol·L– 1 NaOH according to the Gaos method. The total phenolicsand flavonoids in the skin extraction were determined respectively according to the Jia and Meyers method. The pedicel endurable pulling force and berry endurable pressing force were measured by a Digital Push & Pull Tester. In additionthe berry weightberry lengthberry diameterand the content of vitamin C were also determined. All analyses were performed using Excel and SPSS software.

Results:

During the ripening period of the grapes that were treated or not treatedthe L valueand b value decreasedwhile the a valueand CIRG value increasedthe brightness of the grape skin declined and the coloration of the grape skin was transformed from green to red. The grape berries treated with PDJand MeJA had a higher valueCIRG value and a lower value value than the control. The highest valueCIRG value and the lowest value value were found in the grapes treated with 50 mg·L-1 PDJ. At harvestthe CIRG value of 50 mg·L-1 PDJ-MeJA- treated grapes reached 4.61 and 4.50 respectively while the CIRG value of the untreated grapes was only 4.04. During the ripening period of the grapesthe anthocyanin content rose graduallyin contrast to chlorophyll a and chlorophyll b which declined gradually in the grape skin. The content of anthocyanin in the grape skin treated with PDJand MeJA was obviously higher than the control. The 50 mg·L-1 PDJand MeJA treated grapes presented a higher an⁃ thocyanin content than the 10 mg·L-1 PDJand MeJA- treated grapes. The PDJ treatment had a better effect than the MeJA treatment under the same concentration on increasing the content of anthocyanin. At harvestthe anthocyanin content in the grape skin treated with 50 mg·L-1 PDJand 50 mg·L-1 MeJA was respectively 31.2%and 20.0% higher than the control. The content of chlorophyll a and chlorophyll b in the grape skins treated with PDJand MeJA were lower compared with the control. The PDJand MeJA treatments promoted the synthesis of anthocyanin while enhanced the degradation of chlorophyll a and chlorophyll band the coloration of the grape berry improved. The 50 mg·L– 1 PDJ treatment performed best in improving the coloration of the grape berries among all of the treatments. During the period of maturationthe soluble solids content of grapes treated with PDJand MeJA were obviously higher compared with the grapes that were untreated. The 50 mg·L-1 PDJand MeJA treatments were more effective in increasing the content of soluble solids than the 10 mg·L-1 PDJand MeJA treatments. There were no obvious differences between the treated and untreated grapes on the titratable acid content. The application of PDJand MeJA promoted the accumulation of total phenolicsand flavonoids in the skin at harvestand total phenolics in the skin treated with 50 mg·L-1 PDJand MeJA were respectively 36.4%and 29.0% higher than the control. The application of PDJand MeJA significantly enhanced the content of vitamin C in the fruithoweverthe berry weightberry length and berry diameter were not influenced. The grape treated with PDJand MeJA had a higher nutritional qualityin additionthe PDJand MeJA treatment did not have a negative effect on fruit yield. The pedicel endurable pulling force and berry endurable pressing force were not influenced by the PDJand MeJA treatment. The phenomenon of berry drop did not happen in the treated grapes. There was no difference between the treated and untreated grapes on resistance to storage and transportation.

Conclusion:

Two different concentrations of exogenous PDJand MeJA improved coloration and quality of theChristmas Rosegrape berry compared with the control. Under the same concentrationthe PDJ treatment had a better effect than the MeJA treatment on improving coloration and the quality of grapes; the 50 mg·L-1 PDJand MeJA treatment showed a better effect than the 10 mg·L-1 PDJand MeJA treatment. Among all of the treatmentsthe 50 mg·L-1 PDJ treatment was the most effective in improving the coloration and quality of grapes in the trial.

By  SUN XiaowenGAO DengtaoWEI ZhifengGUO Jingnan*CAO Meng
Zhengzhou Fruit Research InstituteCAASZhengzhou 450009HenanChina