Increased Drought tolerance and Resistance to Salinity Through Fungi

Past articles have looked at evidence of mycorrhizal fungi helping plants tolerate salinity, heavy metals and arsenic, and have increased tolerance to acid rain. Here we look at two recent discoveries showing how mycorrhizal inoculation can help plants better survive drought and salinisation.

In one study (Marulanda, A, et al. Drought tolerance and antioxidant activities in lavender plants colonized by native drought-tolerant or drought-sensitive Glomus species. MICROBIAL ECOLOGY), researchers looked at drought-tolerant species of the mycorrhizal fungi Glomus (namely drought-tolerant strains of Glomus intraradices and Glomus mosseae ) and their effects on drought-tolerant Lavandula spica (lavender). Drought tolerant strains of Glomus intraradices showed 35% greater root mass growth in the lavender compared to the regular strains of G. intraradices. And the drought tolerant Glomus mosseae showed 100% greater root mass compared to regular strains of G. mosseae.

Other beneficial effects included an increase in water content in the plant and decreases in antioxidants which would hurt plant health in times of drought. Plants with the drought tolerant strain also had higher levels of nitrogen and potassium compared to the non-drought tolerant Glomus species.

I think one could reasonably expect that the less drought tolerant strains would still be better than an absence of any mycorrhizal fungi. Nevertheless, the drought resistant strains would be a very useful and welcome addition to arid and semi-arid systems.

The following is an excerpt from the study’s abstract:

This study compared the effectiveness of four arbuscular mycorrhizal (AM) fungal isolates (two autochthonous presumably drought-tolerant Glomus sp and two allochthonous presumably drought-sensitive strains) on a drought-adapted plant (Lavandula spica) growing under drought conditions. The autochthonous AM fungal strains produced a higher lavender biomass, specially root biomass, and a more efficient N and K absorption than with the inoculation of similar allochthonous strains under drought conditions. The autochthonous strains of Glomus intraradices and Glomus mosseae increased root growth by 35% and 100%, respectively, when compared to similar allochthonous strains. These effects were concomitant with an increase in water content and a decline in antioxidant compounds: 25% glutathione, 7% ascorbate and 15% H2O2 by G. intraradices, and 108% glutathione, 26% ascorbate and 43% H2O2 by G. mosseae. Glutathione and ascorbate have an important role in plant protection and metabolic function under water deficit; the low cell accumulation of these compounds in plants colonized by autochthonous AM fungal strains is an indication of high drought tolerance.

The second study on the effects of Glomus fasciculatum on the salt tolerance of Acacia nilotica (Giri, B, et al. 2007.Improved tolerance of Acacia nilotica to salt stress by arbuscular mycorrhiza, Glomus fasciculatum may be partly related to elevated K/Na ratios in root and shoot tissues. MICROBIAL ECOLOGY), higher nutrient levels were observed in trees inoculated with the mycorrhizal fungi Glomus fasciculatum where soil was salinated.

The United States Department of Agriculture considers soil over 4 dS/m to be “saline soil.”The study looked at uninoculated trees and inoculated trees at salt levels of 1.2, 4.0, 6.5, and 9.5 dS per metre. In the inoculated plants, higher biomass in root and shoot was observed, showing that fungi assisting in plant growth. Inoculated trees had higher levels of phosphorus, zinc and copper than their uninoculated counterparts. And interestingly, in the lower levels of salt, inoculated trees took up more sodium (1.2 and 4.0 dS/m) than the control trees. At higher levels (6.5 and 9.5 dS/m), the sodium levels decreased whereas the control trees took up more sodium. And as salinity increased, the absorption of potassium in the inoculated trees increased. These results show that Glomus fasciculatum fungi increases the health of Acacia nilotica in saline conditions when compared to uninoculated Acacia nilotica. It is reasonable that this species of Glomus and possibly others could benefit other species of trees in saline conditions as well.

They found that at the higher level of salt (9.5 dS/m), the mycorrhizae had a harder time being established. Designers might offset this somewhat with swales. This would allow fresh rainwater to hold in the soil, reducing the salt content over time. Where salty water tables are a problem, appropriate trees can be used to pump down the water table, thereby removing salt from the upper levels. Whether or not Glomus spp. could help tree species used in this way to pump down salty water tables remains to be seems; but it is very plausible.

The following is the abstract from the study:

A pot experiment was conducted to examine the effect of arbuscular mycorrhizal fungus, Glomus fasciculatum, and salinity on the growth of Acacia nilotica. Plants were grown in soil under different salinity levels (1.2, 4.0, 6.5, and 9.5 dS m(-1)). In saline soil, mycorrhizal colonization was higher at 1.2, 4.0, and 6.5 dS m(-1) salinity levels in AM-inoculated plants, which decreased as salinity levels further increased (9.5 dS m(-1)). Mycorrhizal plants maintained greater root and shoot biomass at all salinity levels compared to nonmycorrhizal plants. AM-inoculated plants had higher P, Zn, and Cu concentrations than uninoculated plants. In mycorrhizal plants, nutrient concentrations decreased with the increasing levels of salinity, but were higher than those of the nonmycorrhizal plants. Mycorrhizal plants had greater Na concentration at low salinity levels (1.2, 4.0 dS m(-1)), which lowered as salinity levels increased (6.5, 9.5 dS m(-1)), whereas Na concentration increased in control plants. Mycorrhizal plants accumulated a higher concentration of K at all salinity levels. Unlike Na, the uptake of K increased in shoot tissues of mycorrhizal plants with the increasing levels of salinity. Our results indicate that mycorrhizal fungus alleviates deleterious effects of saline soils on plant growth that could be primarily related to improved P nutrition. The improved K/Na ratios in root and shoot tissues of mycorrhizal plants may help in protecting disruption of K-mediated enzymatic processes under salt stress conditions.

The moral of the story reaffirms what we already know: Healthy soils with mycorrhizal fungi allow for healthier plants, particularly in difficult situations.

Click for information on Acacia nilotica subsp nilotica.

Keeping The Heat (And Your Money) In

By Douglas Barnes

Winter is well upon us in the northern hemisphere, and here in Canada, staying warm is serious business. We just had the mercury dip to -25°C, and that means more energy expenditure to heat the home. Luckily I got ready back in November with a simple method to change our R-2 windows into R-10 or better windows. Well, at night at least.

The house I am currently in has good southern exposure allowing a lot of sunlight to enter and heat the home in the daytime. This helps heat the home and cuts down on the need for lighting. At night, however, that heat is allowed to escape through the same windows as the R-value of glass, even double pane, gas-filled windows is not very high (they are about R-2). This allows a lot of heat to escape making it necessary to heat the house more in the evening and at night.

The answer to this problem is simple: stop the heat from escaping. The way to do this is with insulating window covers – something that will cover the window after sundown and help hold the heat inside the building.

To do this job, I purchased some 4 cm thick Styrofoam sheeting, duct tape, and weather stripping foam.

After measuring the windows, I cut the Styrofoam to match the size of the window minus 2 times the width of the weather stripping foam, which surrounds the edge of the cover.

After that, the edge of the Styrofoam sheet was taped with duct tape to create a smooth surface for the weather stripping to adhere to. Once the weather stripping was applied, it was stapled in place with a staple gun to make a stronger bond.

When the stripping is fastened in place, the window covers are done and ready to go in the windows.

The Green Tree Foundation

Writing this blog first from Japan then from Canada, it is all too easy to forget that there are regions of the world that are faced with environments that are severely damaged. One such region is Andhra Pradesh, India. Once a lush, sub-tropical environment, it has been reduced by inappropriate land use to drylands with evapotranspiration (evaporation combined with transpiration of vegetation) exceeding rainfall. These dryland environments are the final act before full desertification takes hold.

Luckily for the people of the Anantpur District of Andhra Pradesh there is the Green Tree Foundation. Their goal is the re-greening of the district to provide more food and fiber for the local residents. Their additional aims are to establish more water harvesting infrastructure in the area and, on a global scale, do their part to combat global warming through carbon sequestration.

The Green Tree Foundation has surveyed the local situation to identify the problems faced by the public and used that knowledge to work out strategic solutions to those problems. The most visible strategy employed is the establishment of vegetation in and around villages.

The simple act of planting trees can increase food supply, provide shade, harvest rainfall, repair soil hydrology, increase soil health, and increase precipitation both through capture of condensation and through increased transpiration, leading to increased downwind precipitation.

The man who started this effort is Gangi Setty, a local teacher. Growing up in Andhra Pradesh, Gangi Setty is no stranger to hunger and has seen the local environment grown increasingly arid and impoverished over his lifetime. Since the founding in 2004, he has managed to put together a team of two nursery technicians, two program officers, one civil engineer, one computer operator and about 200 volunteers from locals, who help out in the field with the difficult work of land assessing and planting, to people overseas such as myself who provide technical advice and assist in grant requests.

So far the Foundation has been operating on a budget of approximately 120,000 Rupees, which has come entirely from local donation. That such fantastic results can come out of such a small budget is testament to the sensibility of the Foundation’s strategy of partnering with nature to achieve its goals.

What follows are images of the Green Tree Foundations recent tangible achievements:

Young volunteers getting an almond tree into the ground.

Nursery stock of Arjoon sadura (A.K.A. Terminalia glabra, A.K.A. Terminalia arjuna, edible seeds and the bark is mixed with milk to make a beverage), one of the Bauhinia species (depending on the species, the edible parts can include the nectar, leaves shoots flowers and flower buds, seeds and sap), almond and a plant Gangi Setty identifies as tachoma.

A village leader plants bamboo, excellent for providing food and fiber.

Shade and food are provided for this outdoor kitchen thanks to a bean-covered trellis. The Green Tree Foundation has planted more than 20,000 plants in residential kitchen gardens.

The founder, Gangi Setty, and some volunteers find a strategic microclimate for Cassia fistula (edible flowers, leaves and fruit, also a mild laxative) and Jujupus luluba. Planting on hillsides such as this helps control erosion, goes a long way towards reestablishing the local water table, provides shelter and food for wildlife, and supplies a commons area with food to help provide for the whole village.

A villager walks away with a free Bauhinia tree.

In a very clever strategy to distribute plants, this taxi driver was given saplings to give to his customers.

The foot of this hill has been planted with of Arjoon sadura (A.K.A. Terminalia glabra, A.K.A. Terminalia arjuna).

Kitchen gardens planted providing food and shade.

A Leucaena species going into a strategic microclimate. (These species have edible seeds, leaves and flowers.)

All people of all religions are welcome. Here Muslims take Bauhinia to plant at a Mosque.

Fruit trees stand on what was once barren earth.

Gangi Setty on a street that he has helped to regreen. Shade, food, erosion control and soil rehabilitation are all in place thanks to the efforts of the Green Tree Foundation’s volunteers.

This pharmacist handed out 100 productive trees to people in one day. Such strategies make the regreening effort much easier and more wide-spread.

As a birthday gift, this boy receives a food and fiber source that, with proper care, will provide for his descendants many generations down the line.

Sesbania (a nitrogen-fixing forage tree that also providing edible flowers, leaves and young fruit, and it makes an anti-tumor, anti-helminthic tea) and papaya growing in this kitchen garden.

This teacher took 50 trees to plant at the school.

A group of about 40 volunteers from the Green Tree Foundation dug pits to assist in water harvesting for 700 trees which were planted at the Yogi Vemana channel.

I greatly admire Gangi Setty and his dedicated and knowledgeable team and hope that one day I may travel to Andhra Pradesh to assist in their efforts. But with North America rapidly becoming hotter and drier (parts of the Great Lakes have fallen over 4 feet due to decreased rainfall), and our energy-hungry society facing a future with diminishing energy reserves, the day may come when we may need experienced people like Gangi Setty and his team to come and repair our damaged landscapes.

If you would like to contact the Green Tree Foundation or donate to their cause, they can be contacted at

Gangi Setty, Green Tree Foundation,Poola Bazaar,

Talupula (Post and Village) ,Anantapur Dist,

Andra Pradesh,

India, PIN: 515581

gangisettygtf(at)gmail.com

http://greentreefnd.org/

Read about my project with the Green Tree Foundation HERE

The Green Tree Foundation

An article posted earlier this year was posted specifically to assist India's Green Tree Foundation. The following is a profile of this organisation and the great work they are doing.

PLEASE NOTE: Somewhere along the march of time, the images for this story have decided that they have been on display long enough and have left for a well deserved vacation. We apologise for any confusion this creates.

Writing this blog first from Japan then from Canada, it is all too easy to forget that there are regions of the world that are faced with environments that are devastated. One such region is Andra Pradesh, India. Once a lush, sub-tropical environment, it has been reduced to drylands with evapotranspiration (evaporation combined with transpiration of vegetation) exceeding rainfall due to inappropriate land use. These dryland environments are the final act before full desertification takes hold.

Luckily for the people of the Anantpur District of Andhra Pradesh there is the Green Tree Foundation. Their goal is the re-greening of the district to provide more food and fiber for the local residents. Their additional aims are to establish more water harvesting infrastructure in the area and, on a global scale, do their part to combat global warming through carbon sequestration.

The Green Tree Foundation has surveyed the local situation to identify the problems faced by the public and used that knowledge to work out strategic solutions to those problems. The most visible strategy employed is the establishment of vegetation in and around villages.

The simple act of planting trees can increase food supply, provide shade, harvest rainfall, repair soil hydrology, increase soil health, and increase precipitation (both through capture of condensation and through increased transpiration, leading to increased downwind precipitation).

The man who started this effort is Gangi Setty, a local teacher. Growing up in Andhra Pradesh, Gangi Setty is no stranger to hunger and has seen the local environment grown increasingly arid and impoverished over his lifetime. Since the founding in 2004, he has managed to put together a team of two nursery technicians, two program officers, one civil engineer, one computer operator and about 200 volunteers from locals, who help out in the field with the difficult work of land assessing and planting, to people overseas such as myself who provide technical advice and assist in grant requests.

So far the Foundation has been operating on a budget of approximately 120,000 Rupees, which has come entirely from local donation. That such fantastic results can come out of such a small budget is testament to the sensibility of the Foundation’s strategy of partnering with nature to achieve its goals.

What follows are images of the Green Tree Foundations recent tangible achievements:

Young volunteers getting an olive tree into the ground.

Nursery stock of Arjoon sadura (A.K.A. Terminalia glabra, A.K.A. Terminalia arjuna, edible seeds and the bark is mixed with milk to make a beverage), one of the Bauhinia species (depending on the species, the edible parts can include the nectar, leaves shoots flowers and flower buds, seeds and sap), almond and a plant Gangi Setty identifies as tachoma.

A village leader plants bamboo, excellent for providing food and fiber.

Shade and food are provided for this outdoor kitchen thanks to a bean-covered trellis.

The founder, Gangi Setty, and some volunteers find a strategic microclimate for Cassia fistula (edible flowers, leaves and fruit, also a mild laxative). Planting on hillsides such as this helps control erosion, goes a long way towards reestablishing the local water table, provides shelter and food for wildlife, and supplies a commons area with food to help provide for the whole village.

A villager walks away with a free Bauhinia tree.

In a very clever strategy to distribute plants, this taxi driver was given saplings to give to his customers.

The foot of this hill has been planted with of Arjoon sadura (A.K.A. Terminalia glabra, A.K.A. Terminalia arjuna).

Kitchen gardens planted providing food and shade.

A Leucaena species going into a strategic microclimate. (These species have edible seeds, leaves and flowers.)

All people of all religions are welcome. Here Muslims take Bauhinia to plant at a Mosque.

Fruit trees stand on what was once barren earth.

Gangi Setty on a street that he has helped to regreen. Shade, food, erosion control and soil rehabilitation are all in place thanks to the efforts of the Green Tree Foundation’s volunteers.

This pharmacist handed out 100 productive trees to people in one day. Such strategies make the regreening effort much easier and more wide-spread.

As a birthday gift, this boy receives a food and fiber source that, with proper care, will provide for his descendants many generations down the line.

Sesbania (a nitrogen-fixing forage crop that also providing edible flowers, leaves and young fruit, and it makes an anti-tumor, anti-helminthic tea) and papaya growing in this kitchen garden.

Jordan: The Kafrin Site, Part 2

In Part 1, we saw that the Kafrin site was very arid and extremely salty. In this part, we will look at some of the steps taken by Geoff Lawton and his team to repair the devastated land on the site.

To tackle the problems of extreme salinity and “absolute scarcity” of water present at the Kafrin site, the capture and storage of water was of the utmost importance. As deserts are regions were evaporation exceeds rainfall, reducing evaporation was also of great concern.

To capture every drop of rainfall possible, the site was surveyed to provide a detailed map of the site contours. Once the contour lines were identified, swales (water-harvesting ditches placed on contour) were planned for the site to capture as much of the runoff rain to allow it to sink into the ground where it is most easily stored for the benefit of soil life and vegetation.

There were 8 swales dug into the site with a total length of 1.5 km, and ranging from 2 to 3 metres wide and made 50 cm deep. Additionally, the top swales catch water runoff from the road. The downhill sides of the swales were uncompacted to facilitate water absorption; and they were heavily mulched with organic waste from local farms help combat evaporation. Along the south end of the site, there is an erosion gully. Each swale connects to the erosion gully via pipes to collect the rainfall from them during large rain events, which occur a few times a year.

On the upper side of the swale, fast-growing, pioneering support trees were planted to improve soil conditions. Among the species planted were nitrogen-fixing wattles (also good as poultry fodder), leucaena species (saline-tolerant and good for fodder and fuel), Cercidium microphyllum, AKA palo verde, which is a nitrogen-fixer (also producing edible seeds), nitrogen-fixing casurinas (which can be coppiced for fuel), and nitrogen-fixing Sesbania sesban (which can be used for fodder or fuel and the leaves can be used to make an anti-tumor, anti-helminthic [i.e. anti-parasite] tea).

On the lower side of the swales fruit trees were planted. Among these trees were fig, olive, guava, dates palm, citrus, mulberry, pomegranate, carob, tuna cactus, and grapes. Bananas, the world’s largest herbaceous plant, were also planted on site.

When starting any project, the initial stages require extra care. In this case, the young trees required additional irrigation (apart from rainfall) to get them established on the site. A mulch-covered drip irrigation system was set up to supply each tree with water. The water for the drip system is supplied by a raised goose pond. Nutrient-rich water from the pond supplies “fertigation” for the trees. And as the pond is raised, the water can be moved to the trees without the aid of pumps. Also, the pond itself is shaded to reduce evaporation and provide better shelter for the geese.

The area between the swales is planted with vegetables and grains. The grains include barley for fodder and nitrogen-fixing alfalfa . Organic material from plant production, leaves, stems, etc, is used as mulch to improve soil conditions and help retain moisture in the soil.

As mentioned, there are geese on site, but also chickens, pigeons, turkeys, ducks and rabbits. As the site matured and was able to produce enough forage, sheep and a dairy cow were added.

On site, there is an education centre building made from local materials (sandstone and cob) with sustainability in mind. The character of the building is in keeping with the local aesthetic while having design features appropriate to the climate. The building employs a wind chimney which scoops up oncoming winds and channels them over trays of wet charcoal to create an evaporative cooling effect. From there, the air is drawn out the top of the building via a solar chimney. The stone walls of the building also have a thermal flywheel effect. They slowly draw up the heat of the day releasing it at night, warming the building at night. Then in the morning the stones are cooler than the surrounding air providing a cooler environment during the day. The overall effect is to moderate the extreme desert temperatures.

In Part 3, we will have a look at the results of the project.