Chlorophyll (green) is sequentially broken down into fluorescent catabolites (blue) including FCC, which is converted to FDCC by CYP89A9 (red). FCC and FDCC are non-enzymatically converted into non-fluorescent catabolites (black) NCC and NDCC, respectively.

Amount of chlorophyll in leaf tissue is influenced by nutrient availability and environmental stresses such as drought, salinity, cold and heat etc. Therefore, it has been of special interest to plant scientists to quantify chlorophyll contents in leaves.

Chlorophyll, the pigment responsible for the characteristic green colour of several fruit and vegetables, can degrade to undesirable grey-brown compounds such as pheophorbide and pheophytin. This degradation is mediated by acid and the enzyme chlorophyllase.

Photosynthesis occurs only in plants. 2. Too much light destroys chlorophyll. The unit of light absorbed by the chlorophyll during photosynthesis is the proton.

Plants are supposed to crave sunlight, but too much sunlight can create potentially deadly free radicals. But if the plants are exposed to too much sun, these molecules absorb more energy than they can handle and generate reactive species of oxygen that can destroy the plant.

The roots of the plant take up water but they also need air to breathe. Over-watering, in simple terms, drowns your plant. Soil that is constantly wet won’t have enough air pockets and the roots can’t breathe. Over-watered plants are likely to get root diseases, primarily root rot.

Signs of Overwatered Plants: What to Look For Sign one: If a plant is overwatered, it will likely develop yellow or brown, limp leaves as opposed to dry, crispy leaves (which are actually a sign of too little water). Wilting leaves usually mean that root rot has set in and the roots can no longer absorb water.

Wilting Grass Keep an eye out for signs of overwatering such as leaves and lawns that appear dull and faded, in addition to grass that does not spring back into shape after being pressed down.

Overwatering causes plants to drown from lack of oxygen, or suffer from root rot and fungus because they can’t dry out properly….SIGNS YOUR PLANTS ARE BEING UNDERWATERED:

1. Stunted, slow growth.
2. Brown, dry or curling leaf edges.
3. Flowering plants fail to produce blossoms.
4. Brittle, crisp stems.

Under watering happens when the soil becomes too dry for too long between waterings. Signs of under watering include leaf tips browning, leaves dropping, and wilting of plant and leaves. When plants are under watered, they can usually recover within a few hours after receiving water.

There is never a guarantee that your plant can bounce back from overwatering. If your plant is going to survive, you will see results within a week or so. At this point, you can move your plant back to its original location and resume watering it as normal.

The most common reason that plants’ leaves turn yellow is because of moisture stress, which can be from either over watering or under watering. If you have a plant that has yellow leaves, check the soil in the pot to see if the soil is dry.

If the leaf turned yellow due to overwatering, it’s highly unlikely that the leaf will turn green again. Sorry. Confusing, isn’t it? Underwatered leaves may go yellow on their way to going brown, but whether you’re under or overwatering moisture-stressed leaves are unlikely to go green again.

Should I pick off yellow leaves? Generally, it’s safe to remove a few yellowed leaves from your plant. Removing yellow leaves keeps your plant looking healthy and your garden looking green. Removing yellow leaves can also reduce the risk of pests, which can gravitate to weaker plants.

How to save a dying plant

1. Repot your plant. Use a high-quality indoor plant potting mix to revitalise your plant, and choose a pot that’s wider than the last one.
2. Trim your plant. If there’s damage to the roots, trim back the leaves.
3. Move your plant.
4. Water your plant.
5. Feed your plant.
6. Wipe your plant.

If a plant has not been regularly pruned and has been left to grow in whatever pattern comes naturally, that plant may need what is called a severe cutting back which will result in lots of new shoots and fast growth the following spring.

Poor drainage or improper watering Water issues — either too much or too little — are the leading reason behind yellow leaves. In overly wet soil, roots can’t breathe. They suffocate, shut down and stop delivering the water and nutrients plants need. Underwatering, or drought, has a similar effect.

Abnormal yellowing of leaf tissue is called chlorosis. Leaves lack the essential green pigment chlorophyll. Possible causes include poor drainage, damaged roots, compacted roots, high soil pH, and nutrient deficiencies in the plant according to James Schuster University of Illinois Extension horticulture educator.

When plant leaves turn soft and yellow and start to droop, too much water is frequently the cause. Since plants require both oxygen and water, they become out of balance when excess water prevents the absorption of oxygen.

The most common reason for yellowing or browning of leaves is over or under-watering. It is vital to provide enough time for the soil to dry between waterings. If you have not watered your plant for a long time and soil feels too dry, give your plant a good drink.

Here are few common symptoms and what they may mean:

• Wilting leaves.
• Plant/soil not holding water.
• Yellowing leaves.
• Roots at the surface or coming through drainage holes.
• Tips/edges of leaves turning brown.
• Flower buds form then drop off before opening, or shrivel soon after opening.

Banana tree leaves that are turning yellow and dying indicate that the tree is not getting the nutrients it needs. Inadequate fertilization, poor-draining soil, overwatering and fungal infection are some of the common reasons a banana tree (​Musa​ spp.) might lack nutrients.

The most common cause of yellowing leaves among Dracaena plants is improper soil moisture–in particular, overwatering. Yellow and browning leaves are the first sign that root rot may be occurring. Providing proper and consistent soil moisture is important in caring for a Dracaena plant.

Trim off brown leaf tips or spots with clean shears. Cut off only the damaged tips or spots leaving a tiny margin of brown so not to damage the remaining healthy foliage on the plant. If the entire leaf has turned brown, remove individual leaves at their base. Pull the leaf gently; it may come off on its own.

The most obvious signs of overwatering are soft brown leaves or a soft looking trunk. If you notice this happening, leave your dracaena to dry out fully and then reduce watering going forward.

When you see dead leaves, dormant stems, or brown parts of leaves, cut them away. It’s fine to pluck dead leaves or stems with your hands when possible, just don’t pull too hard or you may damage the healthy part of your plant. For tougher stems or to remove brown leaf tips and edges, use scissors or pruning shears.

Prolonged root rot may lead to death of the plant. In extreme cases, plants affected by root rot may die within 10 days. Root rot is usually lethal although it is treatable. An affected plant will not normally survive, but may potentially be propagated.