Horticulture sustainability exam 2
approaches to biological control
Augmentation is like a surprise bombardation of attack by predator of pest at good time to kill them all relies on continual human management, and not good long term Conservation of natural enemies involves either reducing factors which interfere with the natural enemies or providing needed resources that help natural enemies.
What needs to be considered when trying to be more sustainable
Availability of inputs, climate, farm goals, pests, soil characteristics, topography
Management decisions
Based on profitability, environmental/ social considerations, individual beliefs/goals, lifestyle choices and should promote sustainability and better the environment and community but not at the unacceptable expense to the farmer
Why propagate
Because plants of vegetables are harvested and no more can be reaped, because new ornamentals are needed or desired, or to replace diseased, damaged, old, or dead plants that persists for many years or for new plants to decorate and landscape new areas
How can conventional farmers reduce fertilizer use or be more sustainable
By applying less chemical fertilizer and focusing on soil testing and precision application and supplement with locally available nutrients and cover crops or manure, and compost, and rotations, reduces pollution, runoff energy costs and help profitability
Saltwater contamination of freshwater
By overdrafts of surface and groundwater for agriculture and settles into the earth disrupting natural habitats and water ecosystems
Pesticides
Can enter the ground and surface water and pose threats to the quality and safety of drinking water, at least 1 pesticide is found in any one stream in the USA
Pesticides
Cause unnatural resistance to pesticides due to convolution, creating super pests, leading to more dangerous pesticides that can further damage the land and water and soil composition and natural beneficial microbes living in the land, decrease in pest predators and a rise in secondary pests that damage crops. Pesticide residue is seen in humans, fish, waterfowl, and water.
Cover crops as desirable practices
Clover, rye, vetch, are good cover crops after harvest of vegetables or other horticulture crops, and help prevent so I erosion, increase organic matter, add nitrogen, improve soil quality, weed suppression, conserve soil moisture, improve water infiltration, in orchard Ana divine yards they provide a good environment for beneficial pests
Organic starting forms
Compost Peat moss Sphagnum Wood byproduct
Soil conservation in desirable practices
Conservation tillage, no till, or reduced tillage, cover crops, managing irrigation to minimize runoff, mulching, strip-cropping, windbreaks
Water quality
Contamination with pesticides, fertilizers, salinization all get into the water, reduced inputs help maintain lower levels of pollution IPM, not farming to waters edge, use of organic fertilizers, all help reduce water pollution, buffer zones are great for reducing nutrient overdoing into the water and runoff and improved drainage and flushing can remove field salts but still have contaminated water so it's best to reduce irrigation and more salt tolerant crops,
Cultural Practices: in IPM
Crop unavailable to pests Crop unacceptable to pests Reduce pest survival on crop Alter crop's susceptibility
What is the most widely used form of asexual propagation
Cuttings
Crop marketing
Direct marketing to local venders and farmers markets are good ways to maximize profit, CSA (community supported agriculture )
why do we have weeds in the field?
Disturbance ➨ Low diversity on exposed soil (Empty ecological habitat) First phase - Flush of pioneer plants (weeds) Fill empty niches Protect soil erosion Add organic matter, feed and restore soil life Restore biodiversity Provide habitat for insects and animals
Rural community economics
Farmers are seen as poor and their community too, this is a lack of education and a perspective issue
When use of seed is better?
For annual bedding plants, vegetables being down directly in the fields, or where transplanting is more difficult, then seeds work,
Pathogens from runoff
From feedlots that are treated with sewage, sludge, or manure can contaminate the water supply
Erosion of genetic resources
Genetic diversity is being lost due to the monocultures and fixation of certain traits over long periods of time, the selective germination of certain crops and indigenous plants and crop varieties are being lost.
What happens to the soil with erosion?
Lower crop yields loss of organic matter, silt, clay, decrease capacity to retain water and nutrients soil structure deteriorates rooting depth is reduced.
Air quality in desirable practices
Machinery and chemical application to the fields leaves particles to travel in the dust and around the area and get into the air reduced application of these things helps minimize pollution, IPM also helps reduce pesticide residue in area incorporating crop residue into soil and cover crops and windbreaks can reduce dust from farm machinery and wind erosion and reduces agricultural burning and leads to less smoke pollution
Sustainability and energy consumption
Machines cause fossil fuel pollution, but mostly it's processing and distribution that is the problem, chemically processing nitrogen.
Pesticide management in the US
Main users of insecticide and fungicide are cotton and potato respectively. Pheromones for both control and monitoring were more often used on fruit and vegetable acreage relative to field crops. Pest-resistant varieties were used at relatively higher rates for tomatoes, Strawberries and peaches. Alternating pesticides to reduce resistance was the most common pest management practice among growers of fruits and vegetables.
What are common sources of explant material for tissue culture?
Meristem • Anthers • Leaf pieces (different parts of the plant or flower.)
Artificial soil
More compact to ship, lighter and easy to standardize in terms of content and fertility and can be sure to have no pathogens
Contribute most to soil erosion?
Most soil erosion comes from cattle grazing in the production of crops to feed cattle but 14% of soil erosion comes from horticulture production of crops grown for human consumption in California up to 50% of vegetables and fruits come from there so the soil Erodes 80 times the rate of soil formation
What are the four components of the nutrient medium?
1.Support medium • Liquid or • Semi-solid with Agar or other gelling agent, e.g. Gel-Rite 2. Water 3. Nutrients • Carbon source — sucrose • Vitamins and minerals 4. Hormones • auxins(GROW LONG) , cytokinins(CELL DIVISION in plant root/shoots), gibberellins(regulate growth processes), ethylene(fruit ripening), and ABA(signaling for dormancy/nutrient conservation)
Sustainability issues and soil
Agricultural soil is being lost at a rate of 10 to 16 times that of soil formation this is due to erosion.
Sustainability and water pollution
Agriculture is the most widespread cause of nonpoint source water pollution. poor management of fertilizers irrigation run of pesticides and and animal wastes contribute substantially erosion from croplands contributes roughly 1/2 the sediment in our waterways
Sustainability and water consumption
Agriculture uses 41% of water in us. In some states water consumption is almost entirely by groundwater, and if the use of groundwater exceeds its ability to replenish by at least 25% then there is drought, lack of drinking water, can damage the aquifers
Desertification
Another type of soil complication from wind and water erosion in arid and semi arid regions, and converts crop land to desert land.
When no genetic variation is acceptable is when you use
Asexual cloning, for flowers or fruits that require uniform ripening, size, color, and specific disease and pest resistance
Residues:
Only a minute portion of any pesticide application contacts the target organism. The remainder may degrade harmlessly, but too often water, wind, and soil will carries pesticides to non-target areas and organisms, affecting the health of human and wildlife populations. Public concerns over residues are deepened by the lack of research and knowledge about possible syner- gistic interactions between pesticide residues and the hundreds of other synthetic chemical resi- dues now found in the environment
1. Perennial grain systems
Perennial versions of the major grain crops, cereals, grain legumes, and oilseeds, would offer farmers more opportunities to meet their food and income needs while protecting their natural resources even on lands poorly suited to annual crop production
Inorganic starting materials
Perlite Pumice Sand Styrofoam Vermiculite
Resistance
Pesticide use exerts a powerful selection pressure for changing the genetic make-up of a pest population. Naturally resistant individuals in a pest population are able to survive pesti- cide treatments. The survivors pass on the resistance trait to their offspring. The result is a much higher percentage of the pest population resistant to a pesticide. In the last decade, the number of weed species known to be resistant to herbicides rose from 48 to 270, and the number of plant pathogens resistant to fungicides grew from 100 to 150. Resistance to insecticides is so common — more than 500 species — that nobody is really keeping score (2).
Resurgence
Pesticides often kill off natural enemies along with the pest. With their natural en- emies eliminated, there is little to prevent recovered pest populations from exploding to higher, more damaging numbers than existed before pesticides were applied. Additional chemical pesti- cide treatments only repeat this cycle.``
Which crops are best for diversity
Pick crops best adapted to the soil in the area, local crops, and cultivars that are disease resistant and specialty crops that have high value and things that sell well in the area you are growing
Problems with sustainability
Policy reform policies often his we sustainable agriculture and don't help farmers, don't help with price support, taxes, credits, and lack of educated consumers leads to bad policies and market for farmers
Soil health is key
Preserving organic matter and the composition of the soil helps sustainability and improves soil aggregation, tooth, and microbial life in the soil, it's important to not over till or over apply chemicals that can affect the soil health or microbes living in the soil, or soil pH
Soil
Primarily used outside and not indoors because of soul variations, and it's heavier to ship and can have pathogens
Input reductions for desire able practices
Reduce fertilizers and pesticides but acknowledge that sometimes might be necessary, IPM helps reduce pesticide use, and uses nature as well, it's a great way to ensure economic,health, and environmental risks are all minimized
Water conservation in desirable practices
Reduced volume irrigation systems, using Lower water requiring or drought tolerant crops, leaving fields fallow on alternate years (adoption of dry land farming, and mulches
Crop diversity
Reduces risk of failure from pests, weather, unexpected conditions. Diversification helps gaurs against losing the entire crop, and if market value goes down on one the others might still bring in money, and helps suppress weeds through crop rotation and can also help with disease and pests
The problem with bad soil
Require more fertilizers, chemical applications, pest control, more irrigation,
cabbage caterpillar
Resistant varieties of cabbage: Mammoth Red Rock, Chieftain Savoy, Savoy perfection drumhead Crop rotation: Away from last years crop, over winter in crop debris Soil Management: Larvae/pupae in soil, grow Triticale/Crimson clover
coir vs. Peat
Rich in potassium and a number of micro nutrients •Neutral pH •Holds moisture incredibly well; easy to re-wet when it dries out •Can sometimes contain higher salt concentrations (commercially available coir has been greatly improved in this regard) •Availability may be limited locally peat is Not a source of nutrients •Acidic pH •More difficult to wet; retains less moisture •Can actually restrict germination of some seeds (peppers, in particular) •Readily available; commonly used
Most greenhouse crops are grown in a soilless substrate.
Seeds are sown on a prepared medium that is lightweight, water retentive, and pasteurized. • Soilless media often is composed of: • Sphagnum peat moss • Coir • Perlite • Vermiculite • Composted bar • Tissue culture medi
Types of propagation
Sexual (seeds) and is best for long term storage of plant, but takes longer to harvest and minor variations might be seen, Asexual is through cloning, micropropagation, cuttings, stem, leaf, or other plant part being divisioned and replanted properly, can be a bit more expensive sometimes
Long term erosion problems
Soil is nutrient less and requires fertilizer for growth and productivity, and yields are expected to fall 3% and more
prophylactic holistic IPM
emphasis is on proactive measures to redesign the agricultural ecosystem to the disadvantage of a pest and to the advantage of its parasite and predator complex.
the pyramid of IPM
first avoid the possible problems by managing soil, crop rotations, and beneficial insects to help control pests, the surveillance to monitor crop growth and not attack with pesticides or other things unless pests are actually present, then control, by chemicals or pesticides, or introduction of pest predators.
composted bark
good source of organic matter •lightweight •cheap, available disadv: may contain toxic amounts of manganese •require nitrogen for decomposition
vermiculite (expanded mica)
holds water and nutrients well •does not decompose •is uniform •is reasonably priced •is disease free but holds water almost too much
overcompensation
in potatoes, when there is a certain pest, T. solarnivora then the larval induce the tubers to become more productive to compensate for the pest present in the crops and thus yield is maximized, but its in lower levels that the larval is introduced, and larval regurgitant contains elicitors that induce an increase in potato tuber biomass.
Allelopathy
inhibit weeds by growing cover crops like rye for corn rapeseed for potato, ducks for rice paddy fields,
Integrated pest management
is a broad ecological approach to pest management utilizing a variety of pest control techniques targeting the entire pest complex of a crop ecosystem.
positive defiance
is based on the observation that in every community there are certain individuals or groups whose uncommon behaviors and strategies enable them to find better solutions to problems than their peers, while having access to the same resources and facing similar or worse challenges.`start by enabling people to change their practice, which then changes their attitude, and ultimately they internalize new knowledge.
Biological control
is the use of living organisms —parasites, predators, or pathogens — to maintain pest populations below economically damaging levels, and may be either natural or applied.
push and pull system depends on?
on diversity, rather than pesticides and herbicides, reducing use of chemical inputs and meaning that established push-pull fields have significantly lower costs to farmers than conventional maize farming
when soil health is compromised then pathogen takes advantage which means you need all three things to be compromised
pathogen, environment suitable for pathogen, and proper crop host for pathogen to latch on
how to scape the farm to prevent caterpillar infestation
plant Gaillardia/Dill - attract beneficial insects Intercropping - interferes with host location, oviposition preferences Use transplants: Gives head start against pests Sanitation: Clear crop debris
Three approaches to biological control
predators - other insects or animals that eat the pest parasites - Anthropods, roundworms pathogen - fungi, bacteria
Biointensive IPM
shares many of the same components as conventional IPM, including monitoring, use of economic thresholds, record keeping, and planning. Set Tolerances -how much pest can you take Prevention- clean, appropriate crop and plant placement and management to minimize risk of pest. Monitor and Identify - if you don't know what the pest is or issue, you can't treat it right Control- first bio control through predators, or pathogens that only hurt pest, then if all else fails, then chemical Journal-record what happened and how you dealt with it, so next year you fair better
Burdock - Richard Miller & the Iowa corn farmer - Surviving in the cash economy
sometimes its important not to fight what nature is telling you, so Iowa corn farmer found a niche for the weed that was killing is business and sold that instead "grow what nature wanted him to grow, which was the burdock!"
some predators
spiders, roundworms, birds, ducks, fish, flies, wasps, dragonflies, ladybugs, protozoa, bacteria,
Fusarium wilt of watermelon
symptoms Damping off, leaf yellowing, wilt, rapid death of older plants. Dry, acid soils, temperature 27 oC Races 0 and 1 - widespread Race 2 - restricted to few states Most varieties resistant to race 0 Some varieties are resistant to race 1 None are resistant to race 2
Biofumigation
to harness the natural chemical agents of plants to suppress weeds, fungal pathogens and insects. mustard is a great biofumigation chemical because its glucosinolates also deliver a deadly punch to many soilborne pathogens, nematodes and weeds, making them an effective, all-natural alternative to chemical insecticides and herbicides.
Propagation materials needed
unsalted Unaffected by sterilization or pasteurization good cation exchange capacity and nutrient retention Sufficient density to support seeds or vegetable propagules Proper porosity to provide suitable balance amount aeration, water drainage, and water retention
IPM practices
uses all appropriate pest management techniques such as enhancing natural enemies, planting pest- resistant crops, adopting cultural management, using pesticides judiciously,
the biggest problem for most field crops.
Weeds are More herbicide is used in US farms than insecticide and fungicide. The leading herbicide users are corn and soybean producers.
Sphagnum peat moss
adman: low in salts •slow to decompose •has high water- and nutrient holding characteristics •is uniform and relatively disease free •can be pasteurized disadv: expensive •sustainability concerns •poor public image, especially in UK and Europe
Coir (coconut husk fibers)
adv:slow to decompose •disease free •sustainable disadv: has to be managed due to pH, EC, water and salt content,
weeds
are the most costly agricultural pest category in terms of an dollar losses. Many consider weeds their No.1 pest problem. Volunteer vegetation may be harmful, neutral or even beneficial depending on how it is managed
Reduced-risk pesticides
are used if other tactics have not been adequately effective, as a last resort, and with care to minimize risks
best way to deal with pest is to?
avoid pest by confluence awareness and monitoring the system to keep it healthy, and also developing long, short, and mid term plans for securing crop health
the spread of wheat stem rust UG99 and the native grain crop teff
basically what norman did with wheat rust and how he found wheat resistant Sr31 (Sr for stem rust) that resisted P. graminis. By wonderful good fortune, Sr31 also boosted yields (and not only because plants were impervious to rust).the seed went everywhere but left susceptible for UG99 to attack wheat and it happened.teff was resistant. you need variety and cannot grow only one type of seed because eventually pest and fungi and pathogens will coevolve to become predators to the crops anyway,
Perlite (expanded volcanic rock)
can be pasteurized •provides good aeration •is reasonably priced but is very dusty so you need dust mask
. VRIHI-farmers seed bank, India
diversity is key to sustainability ocal soil and climatic conditions but are also fine-tuned to diverse local ecological conditions and cultural preferences. Crop genetic diversity - A wide genetic base provides "built-in insurance" against crop pests, pathogens, and climatic vagaries. - Unique pigments and fragrance - Double and triple grain rice - Pink rice - high in iron and folic acid - High yield under marginal conditions - Drought tolerance, flood-tolerance (up to six meters), Tolerance to salinity (up to 30 ppt) - Resistance to disease and pests
Genetic vulnerability
Is a threat to the future of crops and plants as they are being selected for and so are their pests,
Agroforestry
Is one way to diversify by also incorporating trees which provide shade to animals, and can be fruit bearing which can bring in more money, and help with wind erosion, can be buffer zones, and help beneficial insects
Propagation
Is the multiplication or increasing of plants in numbers and also involves maintenance of genetic characteristics
Land loss
Land lost to urban use, is often encouraged for farmers to sell land to urban use, land is not protected from public
weed prevention
Have a long, diverse rotation • Sow clean seed • Prevent weed seed formation (mow before bloom) • Avoid imported feeds or manures • Clean thoroughly shared/rented equipment • Compost all manure thoroughly (131 - 170 oF for 3 days) • Control weeds in field borders • Delay planting the crop (for faster crop growth and quicker ground coverage) • Maintain good soil quality, do not fertilize the whole field
proactive strategies for IPM
Healthy, biologically active soils (increasing belowground diversity) • Habitat for beneficial organisms (increasing aboveground diversity) • Appropriate plant cultivars
Soil compaction
Heavy machinery causes soil compaction and hinders water movement in soil, compact soil warms slower and germinates slower and cause nitrogen loss, production costs increase for lack of soil productivity due to bad composition from misuse
Livestock
Helps with food, fertilizer, and can help till land or fertilizer land during offseason and rotatio of land can help rebuild soil,
Runoff and recycled irrigation
Hurts the soil and the sustainability of it but contaminating it reduces yields, when it's saturated with salts, fertilizers and soil causing crop damage, metal corrosion and reduces the water quality for drinking and agricultural use
Consumers and he food market
If the people know why to eat sustainable food then they can help make the farmer more valuable in the eye of government it is important for people to know why they should buy sustainable and what that means for their future their land and their lives, and the impact that has on the immediate environment
Excessive Ph and N
Lead to eutrophication of surface waters, decline in fish populations, reduced quality and can destroy oxygen content leading to hypoxic areas
What do organic materials contribute to media
Increase water rent ion and cation exchange dz
secondary pests
Some potential pests that are normally kept under good control by natural en- emies become actual pests after their natural enemies are destroyed by pesticides. Mite outbreaks after pesticide applications are a classic example.
push and pull system
The push is provided by an African native legume called Desmodium. It naturally produces compounds that have a repellent effect on stem borers, stem borer moths avoid the desmodium (and the maize beside it), and look elsewhere to lay their eggs. The pull in the system is provided by Napier grass, which is planted on the perimeter of maize fields. Stem borers are attracted to Napier grass and prefer to lay eggs on its leaves over maize. In addition to luring stem borers away, the Napier grass is often a reproductive dead-end for the caterpillars, because it has a particularly effective response to stem borer infestation. When the eggs hatch and attempt to bore into the plant, it releases a sticky substance that immobilizes the larvae.
Vegetative propagation is used for
Woody cultivars conifers, deciduous shade trees, fruit trees, roses, perennial vegetables and florist crops
For absolute continuity
The use of sexual cloning techniques are employed
Labor equity
There needs to be better policy and protection for workers and laborer a and consideration for the safety and livelihood of the farmer,
Why are inorganic materials added to mixtures
To improve aeration and drainage