Agriculture

An invasive plant species, or any invasive species, is one that arrives in a habitat it had not previously occupied, then establishes a population, and spreads autonomously (Simberloff 2010a).

It easily adapts to the new environment and grows rapidly until it dominates or “invades” an area by outcompeting and hindering or killing other species, usually the native species.

In Southern Togo, Africa, Radji et al. (2010) reported that 15% of the forest fragments under study were very highly invaded and 31% were slightly invaded.

Most dominant among the invaders is the neem tree (Azadirachta indica).

The introduction of invasive plant species, either native or alien, has become a grave threat to biodiversity conservation.

Many invasives (plant and animal species) have in fact led to the extinction of various species (Simberloff 2010a).

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The process of nitrification is vital in ensuring the availability of the essential element nitrogen to many plants.

This is so when fertilizers that contain ammonic nitrogen (NH4+, ammonium ion) are applied into the soil.

Because the soil particles are predominantly negatively charged, the ammonium ions are adsorbed following the rule that opposite electrical charges are attracted to each other.

But the retention capacity of the soil is affected by its cation exchange capacity which varies with soil texture.

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The Law of Segregation is further explained with the aid of the illustration below.

The illustration uses the contrasting characters smooth vs. wrinkled seeds in Gregor Mendel’s experiments which led to the birth of the modern science of genetics.

The genotypes are provided correspondingly with the capital letter S representing the gene for smooth and the small letter s for the wrinkled character.

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There are many crop plants with edible flowers although, beware, there are also those with poisonous flowers.

These plants necessarily belong to the angiosperms because it is only in this group of plants that flowers are produced.

These flowers are edible in the sense that they or their parts can be eaten or incorporated in food preparation and drinks or otherwise ingested in some manner without adverse health effects.

Some edible flowers or blossoms are largely used as the main ingredients in the preparation of vegetable dishes and raw salads.

But there are other more uses such as for jelly making, flavoring or garnishing, or to add color or aroma with the wide application including in wines and beverages, syrups, vinegars, sauces, pastries, and cakes.

Generally, they are better used fresh but they can also be preserved or processed dry.

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Initial results of Gregor Mendel’s monohybrid experiment on seed form or shape (round- x wrinkled-seeded parents) showed that the cross-fertilized garden peas (F1, his ‘hybrid’) exhibited only one character (he called it dominant) of either parent, that is, the round seededness.

He likewise found that the other parental character (wrinkled seeds) is only hidden in the F1 but reappeared in the F2 and in the succeeding generations.

He called this character recessive.

This observation was also true to the six other sets of characters that he investigated.

He demonstrated that the F2 progeny consisted of two phenotypic types: the dominants and the recessives.

The dominants are those which exhibit the dominant character only while the recessives are those which exhibit the recessive character only.

They occurred in the average proportion of 3:1.

Thus, as to seed shape, 3 were round-seeded and 1 was wrinkled-seeded in every four.

But he did not stop right there.

He proceeded further and made more discoveries.

He continued growing pea plants using seeds harvested in each generation and properly recorded his observations.

Since garden pea is a naturally self-pollinated plant, the next progenies (example F2) are largely selfed progenies of the next preceding generation (i.e., F1).

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Gregor Mendel’s study on monohybrid inheritance using garden pea (Pisum sativum L.) consisted of seven experiments.

Each experiment dealt with a particular character and used two parental types (the pollen source and the seed bearer) which differed in the character under consideration.

These parents had constant characters (purelines) and were crossed artificially.

The resulting hybrids (F1) were then grown and evaluated continuously from generation to generation.

By the time that Mendel read his findings to the Brünn Natural History Society in 1865, he had produced six selfed progenies of the hybrids in Experiments 1 and 2, five in Experiments 3 and 7, and four in Experiments 4, 5, and 6 (Mendel 1865). 

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They should have started planting fruit trees and/or other perennial or permanent crops many years ago.

Their grandparents, their fathers and mothers, and they themselves should have realized long ago that their farms if only planted with the right crops, would have made their lives or the lives of their children more comfortable. 

Unfortunately for them, they did not and so they remain poor farmers whose main preoccupation is corn farming.

It’s not that there’s a tight cause-and-effect case, but it’s what they say.

Such is the common sad revelation of many of those owner-occupants of underdeveloped rainfed farms in far-flung rural areas in South Cotabato, Sarangani Province, and General Santos City (SOCSARGEN).

I happened to be friendly with these farmers.

We call such a corn monocropping system 1-2-1-2 ( or A-B-A-B) meaning that you always start planting to be able to harvest and after harvest, you again repeat the same 1-2 cycle.

At times when rain fails to come, the cycle could even become 1-1-2.

For the outsiders, theirs is a monotonous, exceedingly tiresome, and difficult lifestyle.

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The molave bonsai, as the bonsai using the molave tree (Vitex parviflora) as a specimen is now popularly called, has evolved into one of the favorites among aficionados in the Philippines.

It has now established a niche in the internet world. Its growing popularity was in fact obvious in the 7th Mindanao Open Bonsai Competition & Exhibit held in 2011 in General Santos City.

But up to 1994, my knowledge about bonsai was only restricted to balete (Ficus), which Cebuanos also call “dakit” and the Ilonggos “lonok.”

My initiation into the pursuit of this living art in fact started with my mother’s two balete trees which she grew in deep, ornamental clay pots at home.

These trees remained in those pots for years without repotting, and the roots just kept on rotating around the inside of the pots.

The soil inside had long been depleted, and continuing root growth pushed the trees upward so that much of enlarged bases of roots were visible.

She proudly called these bonsai, anyway.

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Gregor Mendel read his “Versuche über Pflanzen-Hybriden” (Experiments in Plant Hybridisation, translated by the Royal Horticultural Society of London) at the Meetings of the Natural History Society of Brünn in 1865.

It appeared in print in the following year.

Although this paper remained virtually unknown for more than thirty years, it ultimately gave birth to the science of genetics.

Hereunder is a summary reconstruction of some of Mendel’s methodology and part of his observations leading to the Law of Segregation.

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