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Rhizovator™: The root of sustainable production

Background

With a growing world population that needs to be fed and an increased social and urban demand for land, it is no wonder that there is an urgent call for a second Green Revolution to increase the efficiency of food production per unit area in a sustainable way.

Within the Green Revolution there is also a Brown Revolution, which focuses on soil health and the root system. It aims to find ways to enhance root growth as well as nutrient and water use efficiency, including resistance to disease. The Brown Revolution is often called the only sustainable response to the global food crisis.

The Rhizovator™ products

International research found that creating a healthy environment for roots to thrive in and adding natural stimulants could enhance root growth and proliferation dramatically, even doubling water use efficiency and boosting nutrient uptake by up to 400%.

OmniBio™ has developed a range of products under the trade name Rhizovator™ that consists of various stimulants, for instance humate, kelp, amino acids and even microbes, as well as other new and exciting components. These products are tailor-made for specific crop groups and regions. On a case-by-case basis, specific micronutrient combinations are also added to suit site-specific requirements.

The Rhizovator™ products have not only been tested in several greenhouse pot trials with grains and canola, but also in the field on other crops such as table grapes, citrus, soybeans  and cotton.

Effect of Rhizovator™ on crop establishment in the eastern regions

During the 2016/17 season, the new range of Rhizovator™ products were tested in field trials in the Eastern grain producing regions of South Africa.

Figure 1. Improvement of early maize growth seen when Rhizovator™ G1 was applied at planting, near Ficksburg, Eastern Free State
Figure 1. Improvement of early maize growth seen when Rhizovator™ G1 was applied at planting, near Ficksburg, Eastern Free State

Rhizovator™ G1 was applied on maize at planting at a rate of 4 ℓ ha-1 near Ficksburg, in the Eastern Free State, to demonstrate the product’s benefits in improving crop establishment. Treated and untreated strips were alternated, and replicated 10 times. Plants were sampled from each strip three weeks after emergence (V2). Plant height, leaf chlorophyll and aboveground biomass (dry) were measured. The sampled plants were then submitted for tissue analysis so that the total nutrient uptake could be determined. Results were statistically analysed using a paired t-test. There were significant improvements (>90% confidence) in maize growth and uptake of macronutrients (Figure 1 and Figure 2)

Figure 2. Effect of Rhizovator™ G1 on various measures of maize growth near Ficksburg, Eastern Free State

Figure 2. Effect of Rhizovator™ G1 on various measures of maize growth near Ficksburg, Eastern Free State

Figure 2. Effect of Rhizovator™ G1 on various measures of maize growth near Ficksburg, Eastern Free State
Figure 2. Effect of Rhizovator™ G1 on various measures of maize growth near Ficksburg, Eastern Free State

As an investigation, a few strips of Rhizovator™ PC at 4 ℓ ha-1 were also applied on dry beans near Ficksburg, and soybeans near Leslie, Mpumalanga. For both crops a considerable increase in growth was observed (Figure 3 and Figure 4).

Figure 3. Effect of Rhizovator™ PC on dry bean growth near Ficksburg, Eastern Free State
Figure 3. Effect of Rhizovator™ PC on dry bean growth near Ficksburg, Eastern Free State

Figure 4. Effect of Rhizovator™ PC on soybean growth near Leslie, Mpumalanga
Figure 4. Effect of Rhizovator™ PC on soybean growth near Leslie, Mpumalanga

Rhizovator™ trial results in the Western region

In the past 12 months several Rhizovator™ trials were conducted in the western region. Here are some of the very positive results:

Rhizovator™ G1 statistical strip trial on wheat under irrigation on a farm in the Hopetown district

The effect of Rhizovator™ G1 was visible from emergence with a statistically significant increase in the plant population after germination (p=0.048) as can be seen in Figure 5.

Figure 5: Plant population of Rhizovator™ treated plants versus the control
Figure 5: Plant population of Rhizovator™ treated plants versus the control.

With this increase visibly better root growth was also observed (Figure 6).

Figure 5: Plant population of Rhizovator™ treated plants versus the control.
Figure 6: Improved root growth with Rhizovator™ applications

At the four-leaf stage the chlorophyll content in the leaves was measured with a SPAD meter and again the Rhizovator™ G1 had a statistically significant increase (p=0.56) in the leaf chlorophyll content (α=0.1) as seen in Figure 7.

Figure 7. Chlorophyll content in leaves of treated and untreated plants
Figure 7. Chlorophyll content in leaves of treated and untreated plants

OmniSap® samples were also taken at this stage and it was quite clear in the results that Rhizovator™ G1 increased the uptake of macro and micronutrients, as illustrated in this example of paired strip no 9 (Figure 8).

OmniSap® analyses of control versus Rhizovator treated leaves

OmniSap® analyses of control versus Rhizovator treated leaves

Figure 8. OmniSap® analyses of control versus Rhizovator treated leaves

At harvest the Rhizovator™ treated strips showed a statistically significant increase in yield of 320 kg/ha on an already very high yield of 9.85 t/ha! This was at a confidence level of p=0.000012. This means that there is a 99.9% possibility of increasing the yield of wheat under irrigation when applying Rhizovator™ G1.

Figure 9. Yields obtained in the Rhizovator™ wheat strip trial at Hopetown.
Figure 9. Yields obtained in the Rhizovator™ wheat strip trial at Hopetown.

Soyabean Rhizovator™ PC strip trial on a farm in the Bultfontein district.

At this site the effect of the Rhizovator™ was also very clear from the start with much better growth throughout the season. This was proven by measuring the foliage ground cover with the Canopeo app which takes a picture and gives a value of coverage. The Rhizovator™ PC had a statistically significant increase in cover (p=0.1). The effect was also visible in photos taken of the roots at the four-leaf stage. The astounding result can be seen in Figures 10 and 11 below.

Figure 10. Foliage ground cover measurements using the Canopeo app
Figure 10. Foliage ground cover measurements using the Canopeo app

Differences in treated and untreated soya plants at the four-leaf stage.
Figure 11. Differences in treated and untreated soya plants at the four-leaf stage.

As in the wheat trial, the better uptake of nutrients could also be seen in OmniSap® samples taken at the four-leaf stage.

At harvest the Rhizovator™ PC showed a statistically significant increase in yield (p=0.01) and again the increase was constant through al nine paired strips (Figure 12).

Yields obtained in the Rhizovator™ soyabean trial at Bultfontein.
Figure 12. Yields obtained in the Rhizovator™ soyabean trial at Bultfontein.

Rhizovator™ G2 trial results in the Western Cape

During the past two seasons Rhizovator™ was tested on several crops in the Western Cape on cereal as well as permanent crops. Great results were obtained in all instances, indicating how different climate regions and even cultivars react to this product.

Rhizovator™ was developed to specifically target the rhizosphere of plants as most root proliferation is shallower than 20 cm. If the root density is enhanced, water use efficiency (WUE) and nutrient use efficiency (NUE) increases drastically as the rhizosphere influences water utilisation, nutrient availability, root exudates and microbial activity.

Rhizovator™ G2 was applied on cereal crops in a 1:4 ratio (Rhizovator™ to water) and this mixed product was applied at a rate of 20 ℓ.ha-1.

More emerged plants can be seen on the right where the Rhizovator™ G2 was applied compared to the control on the left, where much more open soil can still be seen
Figure 13: More emerged plants can be seen on the right where the Rhizovator™ G2 was applied compared to the control on the left, where much more open soil can still be seen.

The control plants in the front of the picture are much more sparse than the Rhizovator™ G2 plants showing more lush growing plants towards the back.
Figure 14: The control plants in the front of the picture are much more sparse than the Rhizovator™ G2 plants showing more lush growing plants towards the back.

The control plants on the left are much lighter in colour than the Rhizovator™ G2 plants on the right.
Figure 15: The control plants on the left are much lighter in colour than the Rhizovator™ G2 plants on the right.

The Rhizovator™ G2 plants on the left show better vegetative growth as well as root mass and taller plants compared to the control plants on the right.
Figure 16: The Rhizovator™ G2 plants on the left show better vegetative growth as well as root mass and taller plants compared to the control plants on the right. Root growth on the farms used in the trial for the Southern Cape showed a 23% increase on root mass at a confidence level of P=0.04.

Rhizovator™ G2 produced 192 kg grain.ha-1 on average in the Southern Cape, which makes it economical to apply even though it was not a statistical increase.
Figure 17: Rhizovator™ G2 produced 192 kg grain.ha-1 on average in the Southern Cape, which makes it economical to apply even though it was not a statistical increase. This increase was the effect of the increase in root mass, which also had a positive response on ear mass – increased ear mass of 9% were observed (P = 0.15).

Although the Rhizovator™ G2 treated plants initially produced higher biomass, this trend did not continue as the plants matured.
Figure 18: Although the Rhizovator™ G2 treated plants initially produced higher biomass, this trend did not continue as the plants matured, as can be seen in in the graph where the control plants’ biomass were statistically higher (P = 0.07) compared to the treated plants’ biomass. But, regardless of this the Rhizovator™ G2, plants still produced better yields on nine of the 13 strips above (indicated with blue stars).

Despite the higher yields in nine of the strips, quality were not negatively affected by these increases.
Figure 19: Despite the higher yields in nine of the strips, quality were not negatively affected by these increases.

Rhizovator™ PC results in the Western Cape

Rhizovator™ PC was developed for sensitive crops as well as permanent crops, and therefore this product was tested on summer crops in the Western Cape. Newly established ‘Crimson’ table grapes were treated with Rhizovator™ PC in the Montagu region with very good results. The trial consisted of five treatments (in 2015) repeated seven times. The treatments included a control (T1), which received water only every time a treatment application was done, root growth stimulant treatments (Product 1) on its own and in conjunction with growth stimulants (Product 2, which received half the growth stimulant rate, and Product 3, which received the full growth stimulant rate) as well as a test product (T5; Rhizovator™ PC @ 75 ℓ.ha-1). An index was developed to evaluate the growth of the vines as set out in Table 1.

Table 1: Growth index information used to analyse the Chi-square test.

IndexIndex
(cm growth)
Index information
0 0 Dead vine
1 50 Growth ¼ of the distance between the soil surface and the top wire
2 100 Growth ½ of the distance between the soil surface and the top wire
3 150 Growth ¾ of the distance between the soil surface and the top wire
4 200 Vine reached the top wire
5 250 Vine has reached the top wire and grown laterally further on the top wires

Statistical differences were seen for Treatment 5, which was the Rhizovator™ PC (test product), in terms of having the most vines that has grown to the top wire (Growth index = 4) – 53.57% at a 5% level for the Pearson’s Chi-square test – P = 0.05479. The vines in the control (54%) and Product 2 (50%) grew the slowest when compared to the average growth index of 3 (vines has grown half way up to the wire). The test product (Rhizovator™; 79%) had the highest amount of vines at average growth (index 3) or up to the wire (index 4). Product 1 was the only treatment that had vines growing laterally on the wire already.

Growth index representing the amount of vines (n = 28) reaching a specified index (as set out in Table 1) height per enhanced growth treatment.
Figure 20: Growth index representing the amount of vines (n = 28) reaching a specified index (as set out in Table 1) height per enhanced growth treatment.

Vine growth – total length added as well as average growth – of the vines reaching a specified index
Figure 21: Vine growth – total length added as well as average growth – of the vines reaching a specified index (as set out in Table 1) height per enhanced growth treatment. The test product (Rhizovator™) statistically differed from the control with the Fischer’s LSD test. The stem diameter of the test product’s vines were also 9.5% thicker than that of the control vines.

Vines of T5 (Test product; Rhizovator™ PC @ 75 ℓ.ha-1) stayed green longer than the other treatments’ vines, indicating the plants were not stressed, so more nutrients could be taken up by the vines before going into rest.

Treatment 5

Visual vine growth per enhanced growth treatment.
Figure 22: Visual vine growth per enhanced growth treatment.

T5 (Test product: Rhizovator™ PC @ 75 ℓ.ha-1) was also the fastest growing treatment during the 2016 season, even though the difference was not statistical this time. The faster growing vines also did not impact on the yield of the vines. During the 2016 season a sixth treatment was added – Rhizovator™ PC at a very high rate (T6). The lay-out stayed the same for the 2016 season and vines received a second season of treatments similar to the 2015 season. T6 was slotted in between treatments where the buffer sections were.

Note that there are now a T5 treatment referred to as test product, which is Rhizovator™ PC applied @ 75 ℓ.ha-1 and then there is a T6 which is referred to as Rhizovator™ PC. The T6 application rate was however very high (240 ℓ.ha-1) compared to the current recommended rate of 75 ℓ.ha-1. Although T6 was only applied for one season (2016), it produced the highest amount of coloured grapes and all the treatments had more coloured bunches and bigger grape berries than the control. The amount of small green berries of the control was double (41%) that of the rest of the treatments.

Yield produced by applying enhanced growth treatments.
Figure 23: Yield produced by applying enhanced growth treatments.

Treatments 5 and 6 produced the same yield even though T6 received only one season’s worth of applications and that was three times the amount of T5’s application rate, thus indicating that 75ℓ Rhizovator™ PC.ha-1 is adequate for newly established grapes. Product 1 produced a statistically higher yield than that of Product 3 with a LSD (α = 0.05) of 1.919. Considering that these vines were only 17 months old when they produced their first yield, it produced good yields as can be seen in Figure 23 and Table 2.

Table 2: Production variables.

Treatmentn bunches/haAvg. bunch weight (g)4,5kg boxes/ha
Control 14 155 257 802
Product 1 16 668 295 1 068
Product 2 16 271 244 886
Product 3 11 575 243 623
Test product (Rhizovator™ PC) at 75 ℓ.ha-1 13 074 273 847
Rhizovator™ PC at 240 ℓ.ha-1 15 147 255 854

Visual effect of different applications on ‘Crimson’ table grapes.
Figure 24: Visual effect of different applications on ‘Crimson’ table grapes. The size of the berries as well as the colour of the bunches can clearly be seen in these pictures. Product 1, the Test product and T6 (Rhizovator™ PC) has the best colour, while Product 3 shows the lightest colour. This means that Product 1, the Test product (Rhizovator™ PC at higher rate) and T6 (Rhizovator™ PC lower rate) will be riper and marketable earlier in the season compared to the rest of the treatments.

Rhizovator™ PC on cherries in the Western Cape

Rhizovator™ PC was also applied to newly established cherry trees which did not grow properly - so much so that some of the trees died even though all the trees were treated similarly by the producer. Therefore different application rates of Rhizovator™ PC were tested with very interesting results. A Latin square layout with six different application rates were used.

T1 (Control) received water only at every application timing. Treatments 2 (35 ℓ.ha-1 Rhizovator™ PC) and T3 (70 ℓ.ha-1 Rhizovator™ PC) had decreasing amounts of Rhizovator™ PC applied for the four application timings, while T4 (35 ℓ.ha-1 Rhizovator™ PC) and T5 (70 ℓ.ha-1 Rhizovator™ PC) had increasing amounts of Rhizovator™ PC being applied. T6 (50 ℓ.ha-1 Rhizovator™ PC) had the same application rate as Rhizovator™ PC that was applied at all four application timings. Two cultivars, ‘Skeena’ and ‘Staccato’, were included in the trial as they were planted together to improve pollination of trees.

Visual effect of different applications on ‘Crimson’ table grapes.
Figure 25: Visual growth of ‘Skeena’ and ‘Staccato’ cherry cultivars.

Differences in several tree growth parameters when applying different rates of Rhizovator™ PC to cherry trees – ‘Skeena’.
Figure 26: Differences in several tree growth parameters when applying different rates of Rhizovator™ PC to cherry trees – ‘Skeena’. There is a clear trend that the ‘Skeena’ cultivar favours the T3 application rate – 70 ℓ.ha-1 Rhizovator™ PC at a decreasing application rate.

Differences in several tree growth parameters when applying different rates of Rhizovator™ PC to cherry trees – ‘Staccato’.
Figure 27: Differences in several tree growth parameters when applying different rates of Rhizovator™ PC to cherry trees – ‘Staccato’. There is a clear trend that the ‘Staccato’ cultivar favours the T6 application rate – 50 ℓ.ha-1 Rhizovator™ PC at a similar application rate.

It was interesting to see how clear the differences between the cultivars were in terms of which application rates they preferred. The next step will be to calculate if it will also be economical as well as practical to differentiate applications for the different cultivars if the product is applied through the fertigation system. It is also interesting to note that both cultivars clearly did not favour the practice of increasing the application rate of Rhizovator™ PC.

Note on the application of Rhizovator™ PC.

What we have found in the Western Cape, is it seemed that permanent crops prefer to receive the highest application rate of Rhizovator™ PC at flowering. So for fruit trees, start with the highest rate at flowering and then decrease the amount being applied, ie. – 30, 20, 10 and 10 ℓ.ha-1 Rhizovator™ PC at the four application timings or keep applications at a steady rate of 12.5 ℓ.ha-1 Rhizovator™ PC for the four application timings. Apply every second week.

For grape vines however, increase the amount of Rhizovator™ PC for the four application timings. Start at bud break and increase rates, ie. – 10, 15, 20 and 30 ℓ.ha-1 Rhizovator™ PC at the four application timings. Apply every second week.

The benefits of using Rhizovator™                  

    • Better germination
    • Early establishment of seedlings/cuttings
    • Early development of seedlings/cuttings
    • Earlier and increased biomass/chlorophyll production
    • Earlier carbohydrate (sugar)/energy production (ammonium utilisation)
    • Higher root mass
    • Better root proliferation
    • Support of heterotroph microbial growth (carbon and other nutrient source)
    • Better nutrient use efficiency (due to roots and microbe activity)
    • Better pathogen resistance

Rhizovator™ is a dark brown liquid with a density of 1.1 that is applied during establishment or planting. The product is placed over or next to the seed/ seedling/ cutting with a buffer of at least 2cm of soil. The product should never be placed in contact with seed.

The application rate varies between 4 liters and 12 liters per ha, diluted with water at least 5 times. Refer to the specific recommendations for use on the label or with the bulk product.

Speak to your Omnia agent or agronomist to join the revolution today!

Supporting references

  • Daniel Basílio ZandonadiI, Mirella Pupo SantosII. Jader Galba BusatoIII, Lázaro Eustáquio, Pereira PeresIV, & Arnoldo Rocha FaçanhaV. 2013. Plant physiology as affected by humified organic
  • Matter. Theor. Exp. Plant Physiol. vol.25 no.1 Campo dos Goytacazes
  • Łukasz TUHY, Jolanta CHOWAŃSKA & Katarzyna CHOJNACKA. 2013. Seaweed extracts as biostimulants of plant growth: review. CHEMIK 2013, 67, 7, 636-641.
  • Mc Near, D.H. Jr. 2013. The rhizosphere, soil, roots and everything in between. Nature Education Knowledge 4 (3) 1-9.
  • Venant Nihorimbere, Marc Ongena, Maïté Smargiassi & Philippe Thonart. 2011. Beneficial effect of the rhizosphere microbial community for plant growth and health. Biotechnology, Agronomy, Society and Environment 15 (2), 327-337.
  • Verónica Mora, Roberto Baigorri, Eva Bacaicoa, Angel M. Zamarre˜no & José M. García-Mina. 2012. The humic acid-induced changes in the root concentration of nitric oxide, IAA and ethylene do not explain the changes in root architecture caused by humic acid in cucumber. Environmental and Experimental Botany 76 24– 32
  • White, C.A., Sylvester-Bradley,  R. & Berry P.M. 2015. Root length densities of UK wheat and oilseed rape crops with implications for water capture and yield. J Exp. Bot. 66 (8) 2293-2303.

By Dr. Koos Bornman – General Manager: Strategic Agricultural Services
Stephanie Roberts – Regional Manager (Eastern Regions): Research and Development
Johan de Jager – Regional Manager (Western Regions): Research and Development
Marinda Kellerman – Regional Manager (Western Cape): Research and Development